Forum:New 360.... Help!

My roommate and I have been playing Borderlands on the 360 ever since it's release. We have been playing on his system with his hard drive because I didn't have a system. I have finally been able to afford a 360 but now I am unsure of how, if at all, I would be able to get my character onto my hard drive. I really don't want to start a new character and have to get back to level 50. Any way to do this? I'm guessing a memory card but I really don't want to buy one just for this. Thanks for any help.