Has anyone here heard of kettlebells or do any of you use them?

I myself am interested in them although I've never used one. I'd be tempted to get one if I knew the advantage of a kettlebell over other items. I hope someone can enlighten us.

A kettlebell is a cast iron weight that looks like a cannonball with a handle popularised by Russian strongmen (and used on shows like the biggest loser). I would just use dumbbells and barbells as kettlebells are not my thing. (Off course someone brought up with them will disagree).

Absolutely! Kettlebells are an excellent supplement to a workout (though I wouldn't use them exclusively). They can target specific muscles due to the way they're held and lifted. I've gotten especially intense tricep workouts with them (and everybody knows that the triceps aren't fun to exercise). They're also good if you have limited exercise space, as they can allow for a wide range of exercises, from leg work (simply hold them up and do some squats!), to full fledged weight lifting. They also come in a huge range of weights, so you can either start big or work your way up. Another plus is that they're virtually indestructable. Hope that helps!