TheOpenCD.org and GNUWin II
Both of these projects provide a wide collection of free, Open Source software for Windows.

Cygwin
Cygwin is a Linux-like environment for Windows. This program is useful for making ssh connections to the lab computers.

OpenOffice.org
OpenOffice.org is a free and Open Source office suite similar to Microsoft Office. OpenOffice.org consists mainly of a word processor, spreadsheet, and presentation software. It is highly compatible with Microsoft Office formats.