CSS Tips
CSS Tooltips - Part One
http://www.communitymx.com/content/article.cfm?cid=4E2C0
CSS Tooltips - Part Two
http://www.communitymx.com/abstract.cfm?cid=52428
Basic CSS Box Model Demo
http://www.redmelon.net/tstme/box_model/
Are You Too Classy?
http://www.vdebolt.com/ht/classy.html
Why standards-compliant HTML matters
http://evolt.org/article/rdf/17/60446/index.html