Just happened across this little bit of iPhone hackery while investigating some other, more realistic hackery for those of us unwilling to pay $100 a month to AT&T...
A Norwegian programmer built a bootcamp-like program for the iPhone to let you choose between Windows Mobile and the regular iPhone OS.
Pretty nifty, but I have never really heard much good about Windows Mobile, so I'm not sure how many users will really jump on this one. I am impressed with someone hacking a non-Apple OS into a notoriously closed-system Apple device, though.
From Code Retard.