Just passing this out to some of the regulars who don't seem to be keeping up with the thread: Don't forget, you can increase your chances of winning that poster by doing the daily tasks mentioned in the poster giveaway thread. Keep an eye on things as your chances go up pretty high depending on this - and if you don't do any of the tasks your chances will obviously drop due to others doing those tasks!
WON stands for "World Opponent Network" and it was the system that was used back in 1998 to play games like Half-Life and Team Fortress Classic, as well as the countless multiplayer mods that were developed for the Half-Life engine. When STEAM was released, WON was shut down. STEAM was incredibly buggy in it's early does but more importantly, the automatic updates to the Half-Life engine are not optional on STEAM and some of them have made many mods, both single player and multiplayer, unplayable. Fortunately, this did not outright kill the community and it is still alive today, although it is hardly the creative juggernaut it was years ago. planethalflife.com used to feature a mod of the week and faithfully updated that section for years. As far as I am aware, no video game community since has produced new content on the scale that the half-life community did.
What is WON?