Android + Ruby = Ruboto
Charles Nutter, a member of the JRuby team, had an epiphany: because the Android toolchain could convert compiled Java code to Dalvik files, and because JRuby had a Ruby interpreter in compiled Java bytecode, then he should be able to run Ruby on Android. Within an astonishingly short time, he had performed this task, and Ruboto was born. Thanks to the efforts of several other developers, Ruboto has become an active project that is growing increasingly intriguing to Android and Ruby developers alike.
Today, Ruboto comes in two flavors: ruboto-irb and ruboto-core. ruboto-irb is an interactive Ruby shell that runs on Android.