It used to be that upgrading the processor on a Mac was an expensive, difficult, warranty-voiding process undertaken by few Mac owners. Now that Apple has begun the shift to Intel-based machines, upgrading is -- surprise -- an expensive, difficult and warranty-voiding process, made just a little easier by the fact that Intel's Core Duo processors are a little easier to pick up on the open market than the Power PC chips that run older Macs. Japanese magazine Boot has already ripped open a 1.83 GHz Core Duo iMac and replaced the processor with a 2 GHz version, resulting in a 2 GHz iMac. We certainly don't recommend trying this at home -- yet. But when the price of Core Duo processors starts to ease up, we expect to see a lot more Mac modding out there, along with a lot of trashed logic boards done in by overeager first-time upgraders.