Not sure if anyone else has tried this yet, I just got a sim card from my t-mobile blackberry working in my iPad 3g. I'm traveling to europe in a couple of weeks, and thought I would give it a try. I cut down the sim by tracing the shape of the smaller one over it with the edge of a thumb tack, then cut it with a pair of scissors, probably not the best job, but fits well enough, popped it in, plugged in the APN settings epc.tmobile.com, and bam I'm in business! Now of course only edge data here, but when I travel I'm hoping it will get 3G when available. Will test both to see when I'm over there. Hopefully it was save me from some out of pocket roaming costs. Oh, also the sim card still works in the blackberry...the sim card holder on the berry's hold the the card in a different way, so you can position it back over the connection pads and it works no problem. Sweet!