Re: $100 computer suggestions?
I agree used is the way to go. I would try to steer clear of the "Consumer Grade" PCs that cut corners and have sh1tty integrated components. Using a new HD is not a bad idea.
Upgrades can break a good deal. Keep in mind that older memory is typically more expensive than newer technologies. You could spend as much on 512MB of PC100/PC133 as would get you a couple gigs of DDR2. (unless it is a server/workstation board that uses Registered then it is cheap on the used market!) Also do not fall into the Rambus moneypit. Processor prices vary greatly not just depending on speed... if it is a Slot 1 Pentium 3 it is generally more expensive than a Socket 370 Pentium 3.
BTW if you want to build something up I have some older serverboards / cpus / memory I have been meaning to sell, you would have to supply a case / psu / drives
"In theory there is no difference between theory and practice. But, in practice, there is." --Yogi Berra