Specs:
Athlon XP 1700 (retail) - $65
512 Generic PC2100 RAM - $80
Soyo Dragon Plus MB with built in LAN/Sound - $75
Maxtor 740DX 40GB HDD - $40
Sony 48x24x48 CD-RW - $40
Floppy Drive - $10, at most
Antec 1080 Case - if it came with PSU, this should have run you around ~$100-120 at least six months ago
Windows XP Profressional - $300, if you buy retail, $150 if OEM.
GeForce GTS AGP Card - $20-25
Generic Keyboard/Mouse - $20
We're looking at a $500 computer without OS. Of course, this is assuming they were bought new/some used, and the estimates are very generous. Most of the pricing is off of NewEgg...this is a pretty decent deal for whoever is on the recieving end.