Original price: $595
Sold on eBay: From $49 for a specimen with damage to $545 for a machine in like-new condition with the original box, cables, and manuals still wrapped
The best-selling PC of all time featured an 8-bit MOS Technology microprocessor, 64KB of RAM, and a 16-color video palette. You could hook one up to a TV and skip buying a monitor. At the C64's peak, 40,000 of these were rolling off assembly lines each month. The C64 maintains a cult following as fans revive the machines for a round of Centipede or Platoon. Old Commodores, however, are among the items the Computer History Museum does not need donated. Don’t expect your old Commodore to pay for your kid's college, unless it’s rare (like this Commodore 65 prototype that recently sold for $7625).