Android G2 group buy
Androids are compromised by being carrier and operating system locked. You can't travel with them and just swap the SIM card, remove unwanted carrier software, access functions the carrier removed (like tethering via Wifi hotspot), or install updated/custom software (do any devices have commitments to the imminent Android 3.0?). The Nexus One is the best "open source Android" — you have to void the warranty, but root and custom OS installation is just a click away without playing cat and mouse "jailbreaking" games. But the N1 doesn't have a keyboard, a feature many professional and technical people want.
HTC's new G2/Z has a keyboard, and runs stock Android, so it's maybe the best choice as an "open source Android." Perhaps Google will release it as the "N2," though a handset with slightly larger battery and numeric row on the keyboard would be nice. If not, the best best thing could be a group purchase of a particular handset from an unlocked provider (maybe http://www.puremobile.ca/HTC/HTC-Desire-Z-GSM-Phone/ in Canada).
If you're interested, write something in the comments below or stir it up on your favourite site.