My mom bought me one for x-mas this year. All she could find was the xbox 360 arcade unit ($279). I've been looking at the difference between all of them and it seems this one just doesn't have a hard drive. I saw that you can't play old xbox titles without it. Is that the only real difference? It comes with a 256mb memory card, so I can save games and stuff. Does anyone have an xbox without the hdd? Will mine play like shit? I wanna get Halo 3 and Oblivion, I hope I can without the hdd. They're only like a hundred bux. I might even spring for the 120g a few months from now. Anyway...all input is welcome.