For cross-training, I've been playing a lot of pick-up city league volleyball, which, in my humble opinion, is the perfect sport.
Basketball? Pfftt. WAY too much running.
Swimming? Requires putting on a swimsuit... something I avoid at all costs.
Ping-Pong? I could put my eye out!
Golf? Seriously, folks. We're talking about real sports here.
Tennis? Too many balls to trip over.
Skiing? Yeah, right. Flying down a hill faster than a speeding bullet has "just maim me now and get it over with" written all over it.
Bowling? Too much potential to irrevocably embarrass myself.
So, as you can clearly see, volleyball is indeed the perfect sport. I fell in love with the game as a teenager and still would put aside just about anything for the chance to get onto a court for a good, friendly game of volleyball. Nothing relieves a little pent-up aggression like spiking a volleyball down somebody's throat.
My claws come out when I play volleyball. Any other time, you'll get pleasant, easy-going, introverted Me.
But on the volleyball court... your ass is mine.