My big, noisy, hot computer may have to go, in favor of Apple's Mac mini. Two years ago I purchased a Mini-ITX motherboard and put it in a small form-factor case. It works excellent for file-serving, but lacks the power to run desktop applications in something other than twm.
Apple's new computer is small (6.5" by 2"), light (2.9lbs), and has just about everything you'd need. You get 2 USB ports, a CD/DVD-ROM drive, a 1.25GHz PowerPC processor, a 40GB hard drive, Firewire, and DVI output to name a few. One very cool thing is that unlike most budget PCs with integrated video, the Mac mini actually has a decent video card; the ATI Radeon 9200.
My current keyboard, monitor, and multi-button mouse would work fine with this. Add Fink, and you have everything you need.
Actually, I'll drive my 850MHz Athlon ASUS A7V computer into the ground before considering an upgrade. Maybe by then the Mac mini will come with Mac OSX Tiger.