diff --git a/common/content/commandline.js b/common/content/commandline.js
index 4afb62c6..f01cbb0b 100644
--- a/common/content/commandline.js
+++ b/common/content/commandline.js
@@ -1002,12 +1002,18 @@ var CommandLine = Module("commandline", {
         save: function save() {
             if (events.feedingKeys)
                 return;
+
             let str = this.input.value;
             if (/^\s*$/.test(str))
                 return;
+
+            let privateData = this.checkPrivate(str);
+            if (privateData == "never-save")
+                return;
+
             this.store = this.store.filter(function (line) (line.value || line) != str);
             dactyl.trapErrors(function () {
-                this.store.push({ value: str, timestamp: Date.now()*1000, privateData: this.checkPrivate(str) });
+                this.store.push({ value: str, timestamp: Date.now()*1000, privateData: privateData });
             }, this);
             this.store = this.store.slice(Math.max(0, this.store.length - options["history"]));
         },
diff --git a/common/content/dactyl.js b/common/content/dactyl.js
index 68407b8f..c0cce9af 100644
--- a/common/content/dactyl.js
+++ b/common/content/dactyl.js
@@ -164,6 +164,7 @@ var Dactyl = Module("dactyl", XPCOM(Ci.nsISupportsWeakReference, ModuleBase), {
     NEW_WINDOW: "window",
 
     forceBackground: null,
+    forcePrivate: null,
     forceTarget: null,
 
     get forceOpen() ({ background: this.forceBackground,
@@ -955,7 +956,11 @@ var Dactyl = Module("dactyl", XPCOM(Ci.nsISupportsWeakReference, ModuleBase), {
                     });
 
                 case dactyl.NEW_WINDOW:
-                    let win = window.openDialog(document.documentURI, "_blank", "chrome,all,dialog=no");
+                    let options = ["chrome", "all", "dialog=no"];
+                    if (dactyl.forcePrivate)
+                        options.push("private");
+
+                    let win = window.openDialog(document.documentURI, "_blank", options.join(","));
                     util.waitFor(function () win.document.readyState === "complete");
                     browser = win.dactyl && win.dactyl.modules.config.tabbrowser || win.getBrowser();
                     // FALLTHROUGH
@@ -1560,6 +1565,21 @@ var Dactyl = Module("dactyl", XPCOM(Ci.nsISupportsWeakReference, ModuleBase), {
                 literal: 0
             });
 
+        commands.add(["pr[ivate]", "pr0n", "porn"],
+            "Enable privacy features of a command, when applicable, and do not save the invocation in command history",
+            function (args) {
+                dactyl.withSavedValues(["forcePrivate"], function () {
+                    this.forcePrivate = true;
+                    dactyl.execute(args[0], null, true);
+                });
+            }, {
+                argCount: "1",
+                completer: function (context) completion.ex(context),
+                literal: 0,
+                privateData: "never-save",
+                subCommand: 0
+            });
+
         commands.add(["exit", "x"],
             "Quit " + config.appName,
             function (args) {
diff --git a/common/locale/en-US/browsing.xml b/common/locale/en-US/browsing.xml
index de536683..d526ba80 100644
--- a/common/locale/en-US/browsing.xml
+++ b/common/locale/en-US/browsing.xml
@@ -143,6 +143,10 @@
             Like <ex>:tabopen</ex>, but all arguments are opened in
             a single new window.
         </p>
+        <p>
+            When called via <ex>:private</ex>, the new window is a
+            private browsing window.
+        </p>
     </description>
 </item>
 
diff --git a/common/locale/en-US/privacy.xml b/common/locale/en-US/privacy.xml
index db936e49..ee7e6b8c 100644
--- a/common/locale/en-US/privacy.xml
+++ b/common/locale/en-US/privacy.xml
@@ -109,6 +109,19 @@
     </description>
 </item>
 
+<item>
+    <tags>:private :pr</tags>
+    <tags>:pr0n :porn</tags>
+    <strut/>
+    <spec>:pr<oa>ivate</oa> <a>cmd</a></spec>
+    <description>
+        <p>
+            Execute <a>cmd</a> with privacy features enabled, and
+            do not save the invocation in command history.
+        </p>
+    </description>
+</item>
+
 <h2 tag="cookie-settings">Cookie settings</h2>
 <item>
     <tags>:cookies :ck</tags>
diff --git a/common/modules/commands.jsm b/common/modules/commands.jsm
index ba654c44..199cfff1 100644
--- a/common/modules/commands.jsm
+++ b/common/modules/commands.jsm
@@ -915,7 +915,8 @@ var Commands = Module("commands", {
     hasPrivateData: function hasPrivateData(command) {
         for (let [cmd, args] in this.subCommands(command))
             if (cmd.privateData)
-                return !callable(cmd.privateData) || cmd.privateData(args);
+                return !callable(cmd.privateData) ? cmd.privateData
+                                                  : cmd.privateData(args);
         return false;
     },
 
diff --git a/pentadactyl/NEWS b/pentadactyl/NEWS
index d653d640..8912f301 100644
--- a/pentadactyl/NEWS
+++ b/pentadactyl/NEWS
@@ -4,6 +4,8 @@
         all Vim related files.
       - Vimball packages are no longer available.
     • Removed <F1> and <A-F1> mappings.
+    • Add :private command.
+    • Better per-window private browsing support.
 
 1.0:
     • Extensive Firefox 4 support, including: