2. chvatal: Homebuilt AMD K7 Duron Server
This is in the process of being replaced by Knuth.
It consists of:
AMD Duron K7 processor
Some disks, cannibalized from predecessor systems, notably Knuth ;
NetGear Ethernet NIC, also cannibalized from Knuth
Various and sundry DIMM sticks scavenged from other systems
Due to overheating problems with a previous Knuth iteration, this machine has a whole lot of fans.
This machine is running Debian
GNU/Linux, 
Linear Programming by Vasek Chvatal was my main reference to linear programming whilst in both my undergraduate and graduate studies.