Student/teacher edition is semi-affordable.
Also some version of firewall software and anti-virus. I use Norton SW and Norton IS at home on our 5-computer network (*LOL*), we use McAfee at work.

We just picked up a HP media-edition notebook at Best Buy yesterday with two 100Gb drives and a 2.0 Ghz processor and 1Gb of memory...sheesh. For about $1000 less than my 1-year-old desktop.

At least in my chosen profession there are lots of new toys to play with on a regular basis :)