Some prices I got from pricewatch.com at Jan 20, 2001:

Case/power supply: $50
HD 15Gb: $100
HD 30Gb: $110
128Mb PC133: $50
Motherboard Duron/Thunderbird: $90
Duron 650: $50
Thunderbird 850: $110
CDROM 50X: $30
Videocard Voodoo 3 (agp or pci): $90 (completly random,
 I don't know if 2 of this works well on the same computer)
Drive 3 1/2: $10
Mouse: $10
Keyboard (usb/ps2): $20
Monitor 15": $100
Network card 10/100: $20

Sugested configurations:
- Duron 650, 128Mb, HD 15Gb, cdrom, voodoo 3, drive,
  network, mouse, keyboard and monitor.
  Total (per user): $620
  Total (2 users): $1240

- Thunderbird 850, 256Mb, HD 30Gb, cdrom, 2 x voodoo 3,
  drive, network, 2 mice, 2 keyboard and 2 monitors.
  Total (2 users): $960

  Difference: $280

The diference between 2 x single or 1 x dual configuration can,
of course, be completely manipulated to show whatever you want. 
The price curve of computer items have strange patterns as may 
be seen above where HDs with 15 or 30Gb costs almost the same. 
On the other hand, a Pentium III 1Ghz is 5 times more expensive 
than a Celeron 600 and only 2.5 times faster.

Choosing very expensive video card and monitors may lead to no 
savings at all, and even a higher price if you want to put a top 
line processor. Under normal conditions I would expect about 25%
to 30% savings, without considering the administration, 
maintenance and upgrade costs.

Miguel Freitas