Ubuntu Geek posted a guide about installing Unity 2D using PPA in Ubuntu 11.04/10.10

Unity 2D's main goal is to provide a Unity environment on hardware platforms that don't support Unity's Open GL requirements. Many ARM platforms fall into this category, so Unity 2D expands Unity's goodness to a whole new set of platforms.

  Install ubuntu unity 2D using PPA in ubuntu 11.04/10.10 (Demo Video Included)