I just returned from a 2-week trip to Asia, and have an AIS 1-2-Call SIM that someone might be able to use -- it's free to the first reply via PM.

It's got 107 baht on it, and is currently on the 6 hrs of EDGE access for 50 baht/month data plan (it's changeable by calling 1175 customer sevice number). I used the SIM in my unlocked iPhone, and got 130-150 kb throughput consistently in Bangkok and Phuket.

The SIM is valid until July 12, 2008, so please reply only if you can use it before it expires. I'll send it via first class US mail with the booklet (which is in Thai, so it's likely not terribly useful without language proficiency).

Enjoy!