Tools
Here are some handy tools :
Windows
GrabCaptureScreen
A freeware utility which can do a lot of things, something like Snaggit / SnagIt or other shareware crap but this one is completely free. You can download it from this site (see attachments) or from this site where I got it : http://www.cygho.nl/grafisch/screencapture.htm
SP TimeSync
Freeware to syncronize your computer clock with NTP server, handy if you are using Windows 2000 or lower or just want an easy way to change how often it synchronizes with the server. (Original found at http://www.spdialer.com/timesync )
Posix Compliant
vnStat
OpenSource tool to monitor your average bandwidth usage under linux, requires no X and shows graphs using ASCII-style output. (Source: http://humdi.net/vnstat )