Android-Launcher2-Standalone
This is a standalone version of the stock android launcher for 4.1 above. All private APIs are removed so it runs as a normal app. This could be a starting point for anyone who likes to build a customized launcher.
The modification is very easy as Launcher2 doesn't use many private APIs (thanks to android development team!). Trebuchet is another good launcher with more customization options. Unfortunatelly, its use of private APIs make it a bit harder to modify. If you are interested, check my repository of standalone trebuchet.
Source
The original code is copied from AOSP launcher2 tag android-4.2.1-r1.2
Updates
Mar/20/2013 tested on Galaxy Nexus 4.1 and 4.2
License
apache2