Archive.org - a mass of live music, old websites and all kinds of stuff to read and download
Become.com - search service for shopping
Cubscast - excellent Chicago Cubs podcast and forum
Facebook - do I need to explain?
Gutenberg.org - free online books
Info.com - comprehensive search service
Internet Public Library - free online books
Kayak.com - travel discounts
Map My Run - Easy to use site for mapping runs
McMillan Running - running resources
Netvibes - a usefull portal for news and blogs
Pedalling Around - a site documenting the successful effort of Mark Beaumont (a graduate of my alma mater Glasgow University) to beat the world record
for biking around the world. He passed through Wanganui, New Zealand on the 23rd December 2007 and I rode north with him for 40 km or so.
Scottish Malawi Network - a regular newletter about events in the country
Steve Fallon - an excellent site full of information about climbing Scottish hills
The Mountains of Scotland - All kinds of listings of Scottish hills