GotOnTheInter.Net: Random Babble and Misc Adventures

Zac, on the Android Beginners mailing list, has posted directions for using the G1/ADP1 with no sim at all. (This will also allow you to activate it over wifi.) It is not a sim-unlock - that you will have to find elsewhere.

With the release of Nandroid Backup v2.0, infernix brings fastboot backup and restore to anyone with an engineering bootloader (or ADP1.)