Ubuntu for Android (http://www.ubuntu.com/phone/ubuntu-for-android) was a hybrid Ubuntu/Android OS that promised to allow you to use Android as the phone OS, then plug your phone into HDMI and a Bluetooth mouse/keyboard and have a full Ubuntu experience running alongside. It was announced with a lot of splash and got a lot of people excited. The ability to use a phone as a desktop computer on the road was very enticing. But it never materialized, and the source code was never opened (even though it is supposedly "open source", where the heck are you supposed to get the source, or download a build? I can't find one anywhere).
Ubuntu says the reason it never launched is because they need a partner with whom to launch since it needs modifications to Android... er, has Ubuntu ever heard of CyanogenMod?