Someone was looking for a cheap box.  Walmart.com has PCs without any OS.
http://www.walmart.com - then click on Electronics, Computers, desktop PC's.

For $398, you get either: 

AMD Duron processor 1.0GHz
200MHz Frontside Bus
128MB SDRAM Memory
40GB Ultra DMA Hard Drive
CD-ROM Drive
56K Modem
MONITOR - NOT INCLUDED
OPERATING SYSTEM - NOT
INCLUDED
Model No. SYSMAR115

-- or --

Intel Celeron processor 1.0GHz 
100MHz frontside Bus
128MB SDRAM Memory
40GB Ultra DMA Hard Drive
CD-ROM Drive
56K Modem
MONITOR - NOT INCLUDED
OPERATING SYSTEM - NOT
INCLUDED
Model No. SYSMAR116


Not bad for 4 bills.

George