I'm just writing to let everybody know I've written a tool called SMAK that can load Silo .sia or .obj models with UV's and generate ambient occlusion maps for them. It uses the shadow mapping method so it's stupid fast, it generates AO's in less than a minute. I wrote it because there was no good cheap tool that generated AO maps quickly. Eventually I'm going to expand it to load and save more formats, and do lots of utility-type things other than generate AO maps. Here's the website:
http://www.matreyastudios.com/smakHere's an example from the website:

Since it's technically still in beta, I can offer a free copy to anybody who can find any serious bugs or problems with it.