Klanky - You don't have to name a price, but indicating what you have in mind is helpful. Some folks trade game for game, some involve Paypal, some trade for TF2 or other game in-game items.
Behemoth - Plex server
Galactica - FreeNAS
Pegasus - R710 ESX host
fsociety - MBP 15
Rocinante - E5530 testing machine
Saratoga, Ticonderoga, BunkerHill - the Hydra desktop PC-thing.