Ah, you wrote before me...😀
Topic can be closed, answer is here! 😁
The competitions would have hundreds of entrants and some of the prizes were amazing.... ie. $5 buyin one of our Cardschat members (pifan, a long time member who unfortunately passed away) won a trip to Vegas with an entry in a tournament there (I think it was a $1,500 satellite to the Main Event). Tons of other prizes, often the prizepools had $1,000 Added and the winning forum would win a Freeroll for the rest of the forum. They held them on a bunch of different sites.
Look up Online Forum Challenge in the CC search feature and it'll take you back to some threads in 2005 - 2008 (I think they ran til' ~2012)
Cardschat won the OFC events a bunch of times.