Most forums have rules that forbid flaming. This is because the quality of conversation on a forum can be seriously degraded by a flame war. Topics can be "hijacked" by two people who would rather flame each other than discuss the subject of the thread.
Some websites encourage flaming for the purpose of entertainment. One such website is www.flamewarforum.com.
"Where is the funny?"
Any image with these slogans or slogans relating to the forementioned goes good with an image that relates to the image.
Anyhoo, some people devote a forum from their message-board on intentional flame-wars just for fun. But just because it is for fun doesn't make it a total piss-up. The rage felt in flame-wars are genrally believable and occasionally hilarious.