Big Numbers
Age of the Universe
http://www.astro.ucla.edu/~wright/age.html
Age of the Earth and the Universe
http://emporium.turnpike.net/C/cs/agetalk/
Cosmic Mystery Tour
http://archive.ncsa.uiuc.edu/Cyberia/Cosmos/CosmicMysteryTour.html
About Big Numbers
http://pages.prodigy.net/jhonig/bignum/
Large and Small Numbers - Metric Prefixes
http://www.essex1.com/people/speer/large.html