I need to pick up an Apple PowerBook for one of my students to use. He'd be using it for mostly word processing, spreadsheet, and presentations. Possibly some light-to-moderate photo work, and a reasonable chance that he would have to use VirtualPC for one or two Windows dedicated programs. I was thinking about a new iBook (14"), but I've noticed on EBay that there are a lot of used 15" TiBooks running at 500 MHz to 667 MHz, and the occasional 800 MHz, for sale. I like the fact that they have a 1MB cache and the wider screen would be more appropriate. I'd rather get a 867 MHz or 1 GHz TiBook, but not many come up on EBay, and if I end up paying too much, I'd just rather go with a brand new PB for a few hundred more. How do the TiBooks at 667 MHz stand up these days? Still worthwhile? Or are they already too far past their prime? Ideally, I'd like this laptop to last him for the next 3 to 4 years if possible. What about the just discontinued 12" 867 MHz PBs?