diff --git a/Distribution/Gentoo/GHC.hs b/Distribution/Gentoo/GHC.hs
--- a/Distribution/Gentoo/GHC.hs
+++ b/Distribution/Gentoo/GHC.hs
@@ -15,6 +15,7 @@
        , libFronts
        , oldGhcPkgs
        , brokenPkgs
+       , allInstalledPackages
        ) where
 
 import Distribution.Gentoo.Util
@@ -107,6 +108,63 @@
 tryMaybe     :: (a -> Maybe b) -> a -> Either a b
 tryMaybe f a = maybe (Left a) Right $ f a
 
+
+type ConfMap = Map PackageIdentifier FilePath
+
+-- Attempt to match the provided broken package to one of the
+-- installed packages.
+matchConf :: ConfMap -> PackageIdentifier -> Either PackageIdentifier FilePath
+matchConf = tryMaybe . flip Map.lookup
+
+-- Read in all Gentoo .conf files from the current GHC version and
+-- create a Map
+readConf :: IO ConfMap
+readConf = ghcLibDir >>= confFiles >>= foldM addConf Map.empty
+
+-- Add this .conf file to the Map
+addConf          :: ConfMap -> FilePath -> IO ConfMap
+addConf cmp conf = do cnts <- readFile conf
+                      case (reads cnts) of
+                        []       -> return cmp
+                        -- ebuilds that have CABAL_CORE_LIB_GHC_PV set
+                        -- for this version of GHC will have a .conf
+                        -- file containing just []
+                        [([],_)] -> return cmp
+                        rd       -> do let nm = cfNm rd
+                                       return $ Map.insert nm conf cmp
+  where
+    -- It's not InstalledPackageInfo, as it can't read the modules
+    cfNm :: [([InstalledPackageInfo_ String], String)] -> PackageIdentifier
+    cfNm = packageId . head . fst . head
+
+checkPkgs :: String -> String -> ([PackageIdentifier], [FilePath])
+             -> IO [Package]
+checkPkgs msg typ (pns,cnfs)
+  = do putStrLn $ "Searching for " ++ msg ++ "."
+       -- (pns, cnfs) <- brokenConfs
+       unless (null pns)
+                  $ unknownPackages pns
+       (nI, pkgs) <- liftM partitionEithers $ mapM hasFile' cnfs
+       unless (null nI)
+                  $ unknownFiles nI
+       let pkgs' = notGHC pkgs
+       pkgListPrint typ pkgs'
+       return pkgs
+    where
+      hasFile' f = do mp <- hasFile f
+                      return $ maybe (Left f) Right mp
+
+      unknownPackages ps
+          = do putStrLn "\nThe following packages don't seem \
+                        \to have been installed by your package manager:"
+               printList display ps
+
+      unknownFiles fs
+          = do putStrLn "\nThe following files are those corresponding \
+                         \to packages installed by your package manager\n\
+                         \which can't be matched up to the packages that own them."
+               printList id fs
+
 -- -----------------------------------------------------------------------------
 
 -- Finding packages installed with other versions of GHC
@@ -164,34 +222,12 @@
 
 -- Finding broken packages in this install of GHC.
 brokenPkgs :: IO [Package]
-brokenPkgs = do putStrLn "Searching for Haskell libraries with broken dependencies."
-                (pns, cnfs) <- brokenConfs
-                unless (null pns)
-                           $ unknownPackages pns
-                (nI, pkgs) <- liftM partitionEithers $ mapM hasFile' cnfs
-                unless (null nI)
-                           $ unknownFiles nI
-                let pkgs' = notGHC pkgs
-                pkgListPrint "broken" pkgs'
-                return pkgs
-    where
-      hasFile' f = do mp <- hasFile f
-                      return $ maybe (Left f) Right mp
-
-      unknownPackages ps
-          = do putStrLn "\nThe following packages don't seem \
-                        \to have been installed by your package manager:"
-               printList display ps
-
-      unknownFiles fs
-          = do putStrLn "\nThe following files are those corresponding \
-                         \to packages installed by your package manager\n\
-                         \which can't be matched up to the packages that own them."
-               printList id fs
+brokenPkgs = brokenConfs >>=
+             checkPkgs "Haskell libraries with broken dependencies" "broken"
 
 -- .conf files from broken packages of this GHC version
 brokenConfs :: IO ([PackageIdentifier], [FilePath])
-brokenConfs = do brkn <- getBroken -- getBroken
+brokenConfs = do brkn <- getBroken
                  -- Check if we actually have to go look up files and
                  -- do IO.
                  if null brkn
@@ -200,35 +236,19 @@
                            return $ partitionEithers
                                       $ map (matchConf cnfs) brkn
 
-type ConfMap = Map PackageIdentifier FilePath
-
--- Attempt to match the provided broken package to one of the
--- installed packages.
-matchConf :: ConfMap -> PackageIdentifier -> Either PackageIdentifier FilePath
-matchConf = tryMaybe . flip Map.lookup
-
--- Read in all Gentoo .conf files from the current GHC version and
--- create a Map
-readConf :: IO ConfMap
-readConf = ghcLibDir >>= confFiles >>= foldM addConf Map.empty
-
--- Add this .conf file to the Map
-addConf          :: ConfMap -> FilePath -> IO ConfMap
-addConf cmp conf = do cnts <- readFile conf
-                      case (reads cnts) of
-                        []       -> return cmp
-                        -- ebuilds that have CABAL_CORE_LIB_GHC_PV set
-                        -- for this version of GHC will have a .conf
-                        -- file containing just []
-                        [([],_)] -> return cmp
-                        rd       -> do let nm = cfNm rd
-                                       return $ Map.insert nm conf cmp
-  where
-    -- It's not InstalledPackageInfo, as it can't read the modules
-    cfNm :: [([InstalledPackageInfo_ String], String)] -> PackageIdentifier
-    cfNm = packageId . head . fst . head
-
 -- Return the closure of all packages affected by breakage
 getBroken :: IO [PackageIdentifier]
 getBroken = liftM (mapMaybe simpleParse . words)
             $ ghcPkgRawOut ["check", "--simple-output"]
+
+-- -----------------------------------------------------------------------------
+
+allInstalledPackages :: IO [Package]
+allInstalledPackages = do putStrLn "Finding all libraries installed with the \
+                                   \current version of GHC."
+                          libDir <- ghcLibDir
+                          let libDir' = BS.pack libDir
+                          pkgs <- liftM notGHC
+                                  $ pkgsHaveContent $ hasDirMatching (==libDir')
+                          pkgListPrint "installed" pkgs
+                          return pkgs
diff --git a/Main.hs b/Main.hs
--- a/Main.hs
+++ b/Main.hs
@@ -13,9 +13,10 @@
 import Distribution.Gentoo.GHC
 import Distribution.Gentoo.Packages
 import Distribution.Gentoo.PkgManager
+import Distribution.Gentoo.Util
 
 import Data.Either(partitionEithers)
-import Data.List(foldl1')
+import Data.List(foldl1', nub)
 import Data.Version(showVersion)
 import qualified Data.Set as Set
 import Data.Set(Set)
@@ -72,18 +73,17 @@
 
 data BuildTarget = GhcUpgrade
                  | DepCheck
+                 | AllInstalled
                    deriving (Eq, Ord, Show, Read)
 
-getPackages            :: BuildTarget -> IO [Package]
-getPackages GhcUpgrade = oldGhcPkgs
-getPackages DepCheck   = brokenPkgs
-
-getPackages' :: BuildTarget -> IO (Set Package)
-getPackages' = liftM Set.fromList . getPackages
+getPackages              :: BuildTarget -> IO [Package]
+getPackages GhcUpgrade   = oldGhcPkgs
+getPackages DepCheck     = brokenPkgs
+getPackages AllInstalled = allInstalledPackages
 
 allGetPackages :: Set BuildTarget -> IO [Package]
-allGetPackages = liftM (Set.toList . Set.unions)
-                   . mapM getPackages'
+allGetPackages = liftM nub
+                   . concatMapM getPackages
                    . Set.toList
 
 -- -----------------------------------------------------------------------------
@@ -124,6 +124,7 @@
           | CustomPMFlag String
           | Check
           | Upgrade
+          | RebuildAll
           | Pretend
 	  | NoDeep
           deriving (Eq, Ord, Show, Read)
@@ -165,6 +166,7 @@
 flagToAction VersionFlag = Right Version
 flagToAction Check       = Right . Build $ Set.singleton DepCheck
 flagToAction Upgrade     = Right . Build $ Set.singleton GhcUpgrade
+flagToAction RebuildAll  = Right . Build $ Set.singleton AllInstalled
 flagToAction f           = Left f
 
 flagToPM                   :: Flag -> Either Flag PkgManager
@@ -178,6 +180,8 @@
       "Check dependencies of Haskell packages."
     , Option ['u']      ["upgrade"]         (NoArg Upgrade)
       "Rebuild Haskell packages after a GHC upgrade."
+    , Option []         ["all"]             (NoArg RebuildAll)
+      "Rebuild all Haskell libraries built with current GHC."
     , Option ['P']      ["package-manager"] (ReqArg PM "PM")
       $ "Use package manager PM, where PM can be one of:\n"
             ++ pmList ++ defPM
diff --git a/haskell-updater.cabal b/haskell-updater.cabal
--- a/haskell-updater.cabal
+++ b/haskell-updater.cabal
@@ -1,6 +1,6 @@
 Name:                haskell-updater
 Homepage:            http://haskell.org/haskellwiki/Gentoo#haskell-updater
-Version:             1.1.1.0
+Version:             1.1.2.0
 Synopsis:            Rebuild Haskell dependencies in Gentoo
 Description:         haskell-updater rebuilds Haskell packages on Gentoo
                      after a GHC upgrade or a dependency upgrade.