I have similar problems. Most of the suggestions given here haven't worked.
Move the alarm clock across the room? Doesn't make a bit of difference for me. I can unfortunately sleep through a lot and can ignore the alarm (even though it's a really annoying sound that I'm sure my neighbors don't appreciate). Also, when I'm "awake" enough so that the alarm DOES bother me, I usually just get up, hit snooze or turn the alarm off completely, and go back to bed. I'm not sure what's going through my head here, since by going back to bed I'm pretty much ensuring that I'll be late -- but.. that's what I do. Sometimes i repeat that 2-3 times before i actually get up.
Setting the time forward? Tried that, but my mind has never "forgotten" that I set the time to advance, so I'm almost immediately aware that I have more time than the clock says. After a couple days, I don't even think about it and just move up the threshold in my mind of when I have to get up by.
I have a few theories of why it's so difficult for me to wake up. It's mostly self-discipline I think, for me at least. My problem is that ever since high school, I've almost never had to wake up at a certain time. I've had 3 jobs (two at an engineering office, 1 at the University doing programming), and all 3 of these jobs didn't care what time I arrived as long as I get my work done. For college, attendance is almost never a requirement so I would often be late or skip my early morning class. I've found that if it's truly necessary for me to be somewhere on time (for a scheduled meeting, or whatever), I could usually convince myself to get up in time. It still sucks, though, because I can't get anywhere at a decent hour unless it's absolutely critical (read: severe consequences -- I usually accept mild consequences in exchange for extra sleep) for me to do so.
I'm worried what will happen if I ever get a job that requires me to be there at a certain hour, although if my theory is correct I should be able to adjust. I seemed to do okay in high school... and I had to wake up much earlier than I do now.