diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,9 @@
+## 2.9.8
+
+* Add `integrity_`, `crossorigin_` attributes
+* Add `classes_` smart attribute constructor
+* Add `ToHtml (HtmlT m a)` instance
+
 ## 2.9.6
 
 * Fix compilation of benchmarks
diff --git a/lucid.cabal b/lucid.cabal
--- a/lucid.cabal
+++ b/lucid.cabal
@@ -1,5 +1,5 @@
 name:                lucid
-version:             2.9.7
+version:             2.9.8
 synopsis:            Clear to write, read and edit DSL for HTML
 description:         Clear to write, read and edit DSL for HTML. See the 'Lucid' module
                      for description and documentation.
@@ -7,8 +7,8 @@
 license:             BSD3
 license-file:        LICENSE
 author:              Chris Done
-maintainer:          chrisdone@gmail.com
-copyright:           2014 Chris Done
+maintainer:          chrisdone@gmail.com, oleg.grenrus@iki.fi
+copyright:           2014-2017 Chris Done
 category:            Web
 build-type:          Simple
 cabal-version:       >=1.8
diff --git a/src/Lucid/Base.hs b/src/Lucid/Base.hs
--- a/src/Lucid/Base.hs
+++ b/src/Lucid/Base.hs
@@ -162,6 +162,10 @@
   toHtml :: Monad m => a -> HtmlT m ()
   toHtmlRaw :: Monad m => a -> HtmlT m ()
 
+instance (a ~ (), m ~ Identity) => ToHtml (HtmlT m a) where
+  toHtml = relaxHtmlT
+  toHtmlRaw = relaxHtmlT
+
 instance ToHtml String where
   toHtml    = build . Blaze.fromHtmlEscapedString
   toHtmlRaw = build . Blaze.fromString
diff --git a/src/Lucid/Html5.hs b/src/Lucid/Html5.hs
--- a/src/Lucid/Html5.hs
+++ b/src/Lucid/Html5.hs
@@ -9,8 +9,11 @@
 import           Lucid.Base
 
 import           Data.Monoid
-import           Data.Text (Text)
+import           Data.Text (Text, unwords)
 
+-------------------------------------------------------------------------------
+-- Elements
+
 -- | @DOCTYPE@ element
 doctype_ :: Monad m => HtmlT m ()
 doctype_ = makeElementNoEnd "!DOCTYPE HTML"
@@ -457,6 +460,9 @@
 wbr_ :: Monad m => [Attribute] -> HtmlT m ()
 wbr_ = with (makeElementNoEnd "wbr")
 
+-------------------------------------------------------------------------------
+-- Attributes
+
 -- | The @accept@ attribute.
 accept_ :: Text -> Attribute
 accept_ = makeAttribute "accept"
@@ -509,6 +515,9 @@
 class_ :: Text -> Attribute
 class_ = makeAttribute "class"
 
+classes_ :: [Text] -> Attribute
+classes_ = makeAttribute "class" . Data.Text.unwords
+
 -- | The @cols@ attribute.
 cols_ :: Text -> Attribute
 cols_ = makeAttribute "cols"
@@ -537,6 +546,10 @@
 coords_ :: Text -> Attribute
 coords_ = makeAttribute "coords"
 
+-- | The @crossorigin@ attribute.
+crossorigin_ :: Text -> Attribute
+crossorigin_ = makeAttribute "crossorigin"
+
 -- | The @data@ attribute.
 data_ :: Text -> Text -> Attribute
 data_ name = makeAttribute ("data-" <> name)
@@ -628,6 +641,10 @@
 -- | The @id@ attribute.
 id_ :: Text -> Attribute
 id_ = makeAttribute "id"
+
+-- | The @integrity@ attribute.
+integrity_ :: Text -> Attribute
+integrity_ = makeAttribute "integrity"
 
 -- | The @ismap@ attribute.
 ismap_ :: Text -> Attribute