I am NOT a huge fan of the dollar dance. In fact I cringe every time I hear a DJ call for it. I think its a crappy position to put your guest in. They have traveled to your wedding, bought you a gift, hired a baby sitter, etc., and the last thing they need is a nagging DJ telling them how cheap they are.
WHEW ok, there I said it.
If you are a fan of the dollar dance, but maybe want to get a little classier with it, here is something new from the inter-webs. It is "Who get's more cake in the face" How it works? You put two glasses with the Bride and Grooms name on it next to the cake with a little note stating the glass with the most $$$=the Face with the most cake in it!!!!
Ok, so it sounds mean, but heck you can take all that cake in your nasal passages, and that extra cash on your honeymoon. Plus in my opinion (humble) it is less pressure, on your guest and more fun than being groped by an overzealous relative or friend of the family. :)