diff --git a/common/content/commandline.js b/common/content/commandline.js
index 9f71909b..00532bce 100644
--- a/common/content/commandline.js
+++ b/common/content/commandline.js
@@ -538,7 +538,7 @@ const CommandLine = Module("commandline", {
      * @param {boolean} forceSingle If provided, don't let over-long
      *     messages move to the MOW.
      */
-    _echoLine: function echoLine(str, highlightGroup, forceSingle) {
+    _echoLine: function echoLine(str, highlightGroup, forceSingle, silent) {
         this.widgets.message = str ? [highlightGroup, str] : null;
 
         dactyl.triggerObserver("echoLine", str, highlightGroup, forceSingle);
@@ -549,7 +549,7 @@ const CommandLine = Module("commandline", {
         let field = this.widgets.active.message.inputField;
         if (field.value && !forceSingle && field.editor.rootElement.scrollWidth > field.scrollWidth) {
             this.widgets.message = null;
-            this._echoMultiline(<span highlight="Message">{str}</span>, highlightGroup);
+            this._echoMultiline(<span highlight="Message">{str}</span>, highlightGroup, true);
         }
     },
 
@@ -559,7 +559,7 @@ const CommandLine = Module("commandline", {
      * @param {string} str
      * @param {string} highlightGroup
      */
-    _echoMultiline: function echoMultiline(str, highlightGroup) {
+    _echoMultiline: function echoMultiline(str, highlightGroup, silent) {
         let doc = this.widgets.multilineOutput.contentDocument;
         let win = this.widgets.multilineOutput.contentWindow;
 
@@ -567,8 +567,6 @@ const CommandLine = Module("commandline", {
         if (!this.commandVisible)
             this.hide();
 
-        dactyl.triggerObserver("echoMultiline", str, highlightGroup);
-
         this._startHints = false;
         if (!(modes.extended & modes.OUTPUT_MULTILINE))
             modes.push(modes.COMMAND_LINE, modes.OUTPUT_MULTILINE, {
@@ -585,6 +583,9 @@ const CommandLine = Module("commandline", {
         this._lastMowOutput = <div class="ex-command-output" style={"white-space: " + style} highlight={highlightGroup}>{str}</div>;
         let output = util.xmlToDom(this._lastMowOutput, doc);
 
+        if (!silent)
+            dactyl.triggerObserver("echoMultiline", str, highlightGroup, output);
+
         // FIXME: need to make sure an open MOW is closed when commands
         //        that don't generate output are executed
         if (this.widgets.mowContainer.collapsed)
@@ -660,7 +661,7 @@ const CommandLine = Module("commandline", {
         else {
             if (this.widgets.message && this.widgets.message[1] == this._lastEcho)
                 this._echoMultiline(<span highlight="Message">{this._lastEcho}</span>,
-                                    this.widgets.message[0]);
+                                    this.widgets.message[0], true);
 
             if (action === this._echoLine && !(flags & this.FORCE_MULTILINE) && !this.widgets.mowContainer.collapsed) {
                 highlightGroup += " Message";
@@ -1153,6 +1154,17 @@ const CommandLine = Module("commandline", {
         }
         if (this._history)
             this._history.reset();
+    },
+
+    withOutputToString: function (fn, self) {
+        let buffer = [];
+        dactyl.registerObserver("echoLine", observe, true);
+        dactyl.registerObserver("echoMultiline", observe, true);
+        function observe(str, highlight, dom) {
+            buffer.push(dom ? dom.textContent : str)
+        }
+        dactyl.trapErrors.apply(dactyl, [fn, self].concat(Array.slice(arguments, 2)));
+        return buffer.join("\n");
     }
 }, {
     /**
diff --git a/common/content/commands.js b/common/content/commands.js
index c2760018..f4833938 100644
--- a/common/content/commands.js
+++ b/common/content/commands.js
@@ -1241,6 +1241,17 @@ const Commands = Module("commands", {
                 argCount: "1",
                 completer: function (context) completion.userCommand(context)
             });
+
+        commands.add(["y[ank]"],
+            "Yanks the output of the given command to the clipboard",
+            function (args) {
+                dactyl.clipboardWrite(
+                    commandline.withOutputToString(commands.execute, commands, args[0]));
+            },
+            {
+                completer: function (context) completion.ex(context),
+                literal: 0
+            });
     },
     javascript: function () {
         JavaScript.setCompleter([this.get, this.removeUserCommand],
diff --git a/common/content/dactyl.js b/common/content/dactyl.js
index 1b45c777..b9e9df39 100644
--- a/common/content/dactyl.js
+++ b/common/content/dactyl.js
@@ -621,7 +621,7 @@ const Dactyl = Module("dactyl", {
         let br = <>
                     </>;
 
-        dactyl.clipboardWrite(<>
+        return <>
             <item>
                 <tags>{template.map(obj.names, tag, " ")}</tags>
                 <spec>{spec((obj.specs || obj.names)[0])}</spec>{
@@ -633,7 +633,7 @@ const Dactyl = Module("dactyl", {
                         extraHelp ? br+extraHelp : "" }{
                         !(extraHelp || obj.description) ? br+<p>Sorry, no help available.</p> : "" }
                 </description>
-            </item></>.toXMLString().replace(/^ {12}/gm, ""), true);
+            </item></>.toXMLString().replace(/^ {12}/gm, "");
     },
 
     /**
diff --git a/common/locale/en-US/cmdline.xml b/common/locale/en-US/cmdline.xml
index 099368d8..34e166eb 100644
--- a/common/locale/en-US/cmdline.xml
+++ b/common/locale/en-US/cmdline.xml
@@ -210,6 +210,7 @@
                 <li><ex>:vmap</ex></li>
                 <li><ex>:vnoremap</ex></li>
                 <li><ex>:winopen</ex></li>
+                <li><ex>:yank</ex></li>
             </ul>
         </p>
     </description>
diff --git a/common/locale/en-US/index.xml b/common/locale/en-US/index.xml
index cf7c2405..501bbece 100644
--- a/common/locale/en-US/index.xml
+++ b/common/locale/en-US/index.xml
@@ -351,6 +351,7 @@ This file contains a list of all available commands, mappings and options.
     <dt><ex>:winonly</ex></dt> <dd>Close all other windows</dd>
     <dt><ex>:winopen</ex></dt> <dd>Open one or more URLs in a new window</dd>
     <dt><ex>:wqall</ex></dt> <dd>Save the session and quit</dd>
+    <dt><ex>:yank</ex></dt> <dd>Yanks the output of the given command to the clipboard.</dd>
     <dt><ex>:zoom</ex></dt> <dd>Set zoom value of current web page</dd>
 </dl>
 
diff --git a/common/locale/en-US/various.xml b/common/locale/en-US/various.xml
index bdcc3af2..a093cc42 100644
--- a/common/locale/en-US/various.xml
+++ b/common/locale/en-US/various.xml
@@ -110,6 +110,14 @@
     </description>
 </item>
 
+<item>
+    <tags>:yank :y</tags>
+    <spec>:y[ank] <a>cmd</a></spec>
+    <description>
+        <p>Yanks the output of the given command to the clipboard.</p>
+    </description>
+</item>
+
 <h2 tag="privacy">Privacy and sensitive information</h2>
 
 <p>
diff --git a/pentadactyl/NEWS b/pentadactyl/NEWS
index f8c7b909..66e5895f 100644
--- a/pentadactyl/NEWS
+++ b/pentadactyl/NEWS
@@ -83,6 +83,7 @@
     * Added several new options to :map.
     * Added -agent flag to :style.
     * Added :write !cmd and :write >>file.
+    * Added :yank command.
     * Removed the :source line at the end of files generated by
       :mkpentadactylrc.
     * gf now toggles between source and content view.