Intuition Bet- Some books offer in-running betting on some different events. It's very popular in Europe on soccer matches but has a limited following in America. What a book will usually do is offer the betting on certain playoff games in the NHL and NBA and selected football and baseball games such as the Sunday and Monday night games.
For example on tonight's NBA game. The moment the game tips off they constantly change the money line on the side and with the total usually sticking with the original game total and adjusting the juice. For soccer they will have 3 way betting with both sides plus the draw and what side will score next. Prices can change quickly and the books employ a delay so if you try to sneak a play in it will take 7 or 8 seconds and in that time they can block out your bet if something just happened in the game.
Bet365 has a lot of these but the straddles they use would make a loan shark blush.
somebody already mentioned it, but try tradesports. im posting up there myself very soon. a friend of mine was explaining how it works to me, and it sounds fun.
he called it "the crack cocaine of sports gambling".
Concerning tradesports: i actually dont think this got somethink to do with sportsbetting, its like selling stocks, but it doesnt mean i dont like it. Can u make profits there?