Yes, there are sites that track what others are doing. But you run the risk of getting incomplete or stale information. Even the "big guys" can have this problem; how many times have you spotted a "bargain" on Travelocity's
Dream Map, only to be disappointed by
The fare you have selected has changed since the last time it was published.
That said, here are a couple of winners:
http://www.travelzoo.com/ http://travel.yahoo.com/t/specials/