Well I don't know about the real thing but my daughter got me to go on Hula Hoop on the Wii Fit -2 minutes and I was puffing . Even my daughter who was really going for a high score on Hula Hoop Plus said it was really hard and good exercise
So i would guess an actual Hula Hoop would be very good too
Hoola hooping is good exercise. It can help you lose weight, its good for your waist, hips and knees, it helps burn fat at your waist and is also helps with co-ordination. You can buy weighted hoola hoops I think. You can also use the hoop on your legs and arms to tone up the muscles there.
Wii games give you a good option of lots of things, but isn't really exercise. Get a swingball (I love it, pretend it's someone you don't like and whack the hell out of it), Hula Hoop or go for a walk/cycle or if you don't have one, borrow a friend's dog and chase it! Or it can chase you! You can borrow mine!
Wheaten (2 Wheatens available for hire)
i think they're good for toning up your tummy but you will still lose weight doing it on a regular basis. I think the best fun way to lose weight on your tummy is getting a big trampoline. My friend has one and they're just awesome.
Any exercise is good I guess; but the amount you need to do to burn off a few calories suggests not relying on it. For weight loss you'd be more effective concentrating on the input than the output.