Edited Nov. 27, 2007: Check out my new photo-illustrated post on making borax crystal snowflakes.
Before rifling through file folders, binders, and misc. paper piles I took a look online and found the borax crystal snowflake instructions mentioned in my last post. It worked well and was really pretty until, being deemed to large and annoying for a rear-view mirror ornament, it was left on the dash and baked in the hot sun. It became a less beautiful colour and very crumbly.
Have fun growing snowflakes!