Piano, clarinet, tenor saxophone and drums.
Used to play anime themes on the piano a lot, but then I stopped because playing them didn't really sound/seem impressive and/or worth my time. Felt like I was doing my piano a disservice.
On the other hand, my best friend's younger brother plays anime theme songs all the time and focuses all of his piano lessons on them and with his COMPLETE LACK OF ANY TECHNIQUE, he would play stuff like the Gundam SEED OP1 and the Chrono Trigger themes and be smug about it. "I can play these songs and YOU can't~"
God, thinking about it rekindles my hatred and urge to punch that fat chubby faggot in the face.