Trombone, since it's what I play in all four of my school's bands.
And any kind of guitar, really. I like electric just because I love rock music, and love the sound an electric guitar can make. I like bass because it has a more subtle and less noticeable sound most of the time, but it's still incredibly important to music. (Seriously, turn all bass off on a song and listen to it. Rarely as good.) And acoustic because it's the only one I can play, and I like the more natural sound it has than other guitars.
Mine is the piccolo. I'm pretty good at playing it and I love playing it. A couple days ago, after not playing it for several months, I played it and I was still pretty good at it