Re: Workout/Staying in Shape Thread
Abs: Crunches (and the various crunch variants), plank, side plank, russian twist, leg raises.
Triceps: Dips, Push ups and variants work your chest and triceps (among other things)
Biceps: Pull ups
to be honest, i wouldn't just leave it at just working your arms and abs. Squats, even if they're free weighted, lunges etc will also be of benefit. IMO everyone should squat or at least do some lower body strength exercises, even if its not your goal right now, learning proper squat technique is important, and has far more real world application than any other exercise you can do.