Can someone confirm, that an iPhone does all the things it's supposed to (except for calling) without a SIM card?
I mean: can I use it like an iPod, or does it need a SIM card to start up, and let me access all built-in programs?
OTB no, and they dont work with PhaseII SIMS (if your not in the industry they are orga test SIM's which bypass locks on handsets, so you can check menu's and settings on locked handsets with out the correct network SIM for example) ALL other handsets will work with PhaseII's or WinMo handsets power up without SIM's
I think you may be mistaken. Any iPhone which has been activated can be used without a SIM card. I took my SIM card out of the phone when I went to Europe just to be extra sure I wouldn't receive any ridiculously expensive roaming bills. You can use wifi and all other features.