Another vote for p90x, great workout.
I'm also a big fan of running, well actually I f*ckin hate it but the results are great. Especially if you live near sand. I'm 2 minutes from lake Michigan so I do my running in the sand dunes. Add some light ankle and hand weights and you'll be a lean mean birdie machine in no time.
Plus whenever you see sand you'll finally know what it means to feel pure hate