Today I have some pictures of the coolers I'll be using on the GTX280's. This is the SilenX IXG-80HA2 Noiseless GPU Cooler. They have an optional fan kit, which I bought, Ixtrema GPU Fan Kit. But I won't recommed the fan kit, it's expensive, flimsy and the fans are totally exposed. Instead I bought (4) Scythe Kaze-Jyu Slim 100mmx100mmx12mm 2000 rpm 27.6 cfm fans, (2) for each card. On a side note, these fans come with brackets to mount them onto a hard drive.
Here are the basic spec's of the Coolers
dimensions - 228.4x113.2x33.2mm
base material - Copper Heatpipes, Aluminum Plates
fin material - Aluminum Fins
fin surface area - 2800cm²
weight - 365g
gpu compatibility - Most Radeon and GeForce graphics cards with mounting holes, SLi and Crossfire supported
While they say the Cooler is Crossfire and SLI compatible, it is only compatible as a fanless alternative. If you want to use fans with these Coolers you'll be looking for a new case, probably.