If you ever decide to pursue graduate study in the US (I am unsure about foreign institutions) you will surely find yourself writing a Statement of Purpose. It is a document required by nearly all institutions. In it you should convey three essential things:

zero: What has compelled you to undertake graduate study.
one: What makes you excellent. Why you should be selected from amongst all the other candidates.
two: What you intend to research/study in terms that are as specific as you can mannage.

Some resources that I have found scattered about the net:
http://www.accepted.com/ -- A site dedicated to this kind of thing.
http://www.coe.berkeley.edu/cues/grad.purpose.html -- A helpful howto put together by Dr. Carla Trujillo at Berkeley.
http://phd.stanford.edu/ -- An amusing comic about grad students and some good links as well.
More as I find them.

Note that this node may be slightly biased toward more technical fields. Forgive me but I can only node what I know.

Ironicly I should be writing my Statement of Purpose right now instead of noding. Any advice by my fellow everythingians is greatly appreciated.

Update: 26 January 2001
I was accepted to the PhD program in Computer Science at Purdue University today.
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