Forum based games allow you to do table top gaming without all having to be in the same place at the same time. Instead of verbally acting out your actions, you type them in. Yes, it is very, very slow, in comparison to a table top game. However, if you work at odd hours or are not near any games, it is a god send.
You can see a good one at www.rpol.net
, contemporary, Slayer's dream- a Buffy game.http://rpol.net/rpol/game.cgi?gi=210&gn=Slayer's+Dreams+A+Buffy+the+Vamp+Slayer+Game&date=1065075043
Freeform gaming, in my opinion is a little strange. It is more like writing a cooperative story than playing a game. But it makes people happy, so they do it.
While you can play by post here, most of the discussions deal with ideas you can use in a table top roleplaying game.
We have four worlds/ settings being developed, a number of ideas being fleshed out below for setting or magic systems, and about 37 articles on a variety of gaming subjects.