Tell me about it.... I started putting one together with spare parts I had laying around.... Then I needed DX9 for MCE (had an ATI AIW8500), Then I needed a nice looking case, then a matx motherboard to fit in it. Then a different CPU since the AthlonXP motherboards were expensive and it was cheaper to get A64 stuff. Then I wanted a HDTV tuner, then the bill was $800 Just do it in increments, get the basic stuff now, and upgrade later! You don't really need a super CPU except maybe to play the newer mame games. You don't need a TV tuner, you could use 1 stick of 1gig memory for now and get another later (which is plenty anyways), you might have a older HDD laying around (10 or 20 gig if you keep the files on the Cab).