Informal trading communities

There are several lesser known sites known that specialize in a multitude of services including community trading, but not limited as such:
Craig's List is a site for posting personal advertisements but many users have found this a less than conventional means of trading goods online with local residents. 1UP is a website dedicated to the publishing of news, videos, and other related media dealing with video games. There is a growing section of the site though dedicated the trading of games and DVDs on their message boards. IGN is another website dedicated to videogame news and media that also has message boards dedicated to online trading. The distinguishing factors being that IGN has a much larger integrated database of games and DVDs in existence that users can add to their collection lists for trade purposes as well as mark the ones they are playing to lock from trade.
General rules of conduct
Some online trading communities have specific rules adopted by the users of that community, and though they can differ most have settled upon a few standard practices:
The less experienced trader (usually indicated by their feedback or trade history) sends their half first. It is generally frowned upon by most communities to "thread crap" (A term referring to a user not involved in the pending trade undercutting a trade in progress with either a better deal or reasons for the trade not to take place). When trading any used items be sure to include the condition and quality of the product so as the receiver can determine the overall value of it.