Dave Doering links:

http://www.zillow.com/ - Real Estate info

http://spamhole.com/ - temporary e-mail addresses
(Another site: http://www.spambob.com/)

http://farecast.com/ - Airline fare patterns

http://dynamism.com/ - Foreign tech products

http://absurdlycool.com/ - Freebies Finder

http://www.netflix.com/ - DVD rentals

http://ocwconsortium.org/ - Online classes

http://death-watch.com/ - Celebrity deaths (not sure I got this link properly)

http://www.skullsunlimited.com/ - Medical

http://anatomical.com/ - Medical