CANGAROO is an array of Cherenkov telescopes near Woomera, Australia that aims to study the gamma radiation emitted by celestial bodies, including among other things the wisps of matter left over from supernovae, in the hope of finding out just where the heck it's all coming from. It's a collaborative project between various Australian and Japanese universities and the High Energy Accelerator Research Organization (KEK). None of that is very important though.
What's important is that CANGAROO stands for "Collaboration of Australia and Nippon for a GAmma Ray Observatory in the Outback", possibly one the awesomest acronyms ever. It cheats a bit, with the double-initial GAmma and what with "cangaroo" not strictly being a word, but come on. Someone stayed up all night coming up with that, and credit where credit is due.