Meanwhile, people continue to push the envelope as far as the iMac's upgradability is concerned. The iMac, as designed, is one of the least expandable computers on the market today: it has zero expansion slots (at least, officially speaking), no SCSI, no ADB, no "standard" serial ports, no additional drive bays-- in fact, just about the only thing that you are supposed to be able to upgrade is the RAM. That doesn't mean that people haven't come up with some pretty ingenious ways of making the iMac into something other than that which Apple conceived. We've heard of all kinds of horseplay, like soldering floppy drives to the motherboard and adding arcade-quality 3D gaming support via the undocumented "Perch" slot. And now that LinuxPPC has preliminary USB support, you've even got people out there running Unix on Apple's beloved "consumer" machine. The bottom line is this: the iMac is too cool to be left alone. It beckons geeks bearing soldering irons and chewing gum; to them, the iMac just begs to be hotrodded up.

There's one area in which we hadn't heard of any compelling hacks, though, and that's the field of processor upgradeability. For instance, the PCI PowerMacs (with the exception of the 7200) had their processors on a daughtercard, allowing an easy upgrade to a faster chip; popping a G3 into a 7300 is a piece of cake. The PowerMac G3's took a slightly different route; no daughtercard, but the chip's in a ZIF socket, making it a pretty simple matter to replace it with a zippier processor, which you can purchase from any number of third party manufacturers these days. But the iMac is a little tricky. From what we've heard, the iMac's processor is on a daughtercard, but it shares that daughtercard with the Mac's hardware ROM. Since the ROMs for the iMac have to come from Apple, that makes third-party processor upgrades for the iMac a tough thing to pull off. At least, that was our impression.

However, if iMac2Day can be believed, some company called Terrahertz International has an iMac processor upgrade for sale right now. For just $250, you can pick up a Terra 266/G3 iMac Speed Kit as a Christmas present for your funky blue friend. Not only do you get a 266 MHz G3 processor module that (somehow) works in your iMac, but you also get a 64 MB memory module and Mac OS 8.5. (Note that current iMacs already ship with Mac OS 8.5 pre-loaded, and owners of previous iMacs qualify for a $20 upgrade from Apple. Still, it's kinda cool.) Sounds like you get a lot for your $250. We don't know how it works, and in fact there isn't even a website to visit-- to order, you actually have to send them email or a fax. How 1996! But hey, if it's all legit, this could be the start of some serious iMac speed upgrades to come.