What is your favorite exercised that works??

I like the elliptical. I keep it interesting by doing intervals of high intensity and medium intensity. I usually use music as a guide, so the intervals last about 2-3 minutes. I also found trainer (just use her occasionally since it's expensive) who gave me a great workout that keeps my heartrate up and doesn't require any machines. It kicks my butt, but I love the variety.

Weight lifting! I looooooooove it and I look AMAZING and ridiculously fit. I almost never do cardio.

Here is a typical week's worth of work out for me:

Mon: 30 min elliptical, weights
Tue: 60 min Latin Heat (Zumba) class
Wed: off
Thu: personal training - 30 min weights/lunges with trainer, 30 min elliiptical/bike on my own
Fri: 30-45 min elliptical
Sat/Sun: 30-45 min elliptical or bike, or long long walk around lake (weather dependent)

My off days sometimes vary but I usually work out 4-5 days/week. I want to start spinning too - I need to keep my workouts varied otherwise I get really, really bored.

Water aerobics got me started.  You stay cool and don't get sweaty, everyone is more like me (rather than the 20 year old cuties in the weight room), low impact, you can be uncoordinated or modify your movements and nobody can tell from the neck up, if you lose your balance you don't embarrass yourself...

It kicked my butt at first, but now I need to modify the workout to challenge myself more.  It helped me to build to better endurance for running and cycling.

And it's FUN!