Sauna Belt - that's an old scam that comes out every few years. I googled and found an ad for it that says it "helps you to sweat away unwanted fat, eliminate cellulite, lose weight and ease muscle pain – all while sitting in the comfort of your own home...focuses the sauna heat on the most problematic body parts to help flush out and eliminate toxins"
Basically, all you're doing is sweating away WATER - *NOT* fat or cellulite (which is just fat anyway). Any weight lost using this device will come back as soon as you drink water.
6 Second Abs and Ab Lounge are two devices that are supposed to get everyone that six pack they want.

Rather than purchasing these gadgets - there are an INFINITE amount of abdominal exercises that you can do for *free* using just your body weight or something like a medicine ball (or give Pilates and/or Yoga a try!)
Besides, to get smaller abs, what's REALLY required is to watch your calories - as has been said many times in our Ladies who Lift forum "Abs Begin in the Kitchen".
If you *must* buy one of these items, I advise checking eBay or Craigslist.org (or your local penny saver) for a deal on a USED one. Why get taken for the entire price?