DZF was the first forum that went down, although to be fair it was operated by the FBI. They busted several of the vendors on it, particularly they seemed focused on people selling opiates. Other than DZF and TFM I don't think any other forum has had an entire operation against it or substantial busts related to it. Of course individual members on several forums have been busted due to interceptions, but as far as actual operations aimed at internet drug dealing forums go, DZF and TFM are all that I am aware of. Of course I am speaking in terms of recreational drug forums, there have been two other major operations against online drug dealing communities though. The first of which was operation webtryp which targeted vendors selling research chemicals (although no forums, they operated from their own independent websites), the second of which was operation raw deal which targeted the steroid forums.