We pilates people LOVE talking about the pelvic floor. We love it because your abdominals and the pelvic floor have a symbiotic relationship, when pelvic floor is working, so are your abdomials.
Here is a great little device marketed as a sex toy, but is a great and legitimate tool for strengthening the pelvic floor! Its simple to use: grab a little lube, insert the balls and just hold them in. You can add pulses, stand or squat to increase difficulty. I always love an exercise that you cant do wrong!
Progressive physical therapists have started using tools like this for woman who have non-responsive pelvic floor (a pelvic floor that just wont work) or for women strengthening back up after childbirth. And the coolest part, it really will give you a better orgasm, its not just hype.