I once had a girl in California ask me to wire her money. Funny thing was, she got me on AIM and we even talked on the phone before she hit me with her sudden "I need money now" tragedy that related directly to a story she told me over the phone. It was a very well thought out scam that I know a lot of guys would have fallen for, but the point is simple:

The last thing you want to do to somebody you are trying to impress over the internet is ask them for money; so as far as I am concerned, it's always a scam.