Education

W3Schools
Useful resource for HTML style and formatting in HTML among other things
http://www.w3schools.com/
Coursera
An initiative to provide free educational courses
https://www.coursera.org/courses
WebMonkey
Design techniques blog and HTML/CSS cheat sheets
http://www.webmonkey.com/
Correct English
A useful listing of common mistakes in written and spoken English
http://www.wsu.edu/~brians/errors/errors.html
TED
Inspiring educational talks on pretty much everything from cell cultures to culture
http://www.ted.com
Campus - Google start-up support
Useful presentations and classes about new media 
http://www.campuslondon.com/events/
General Assembly - New media training
Training courses about new media, technology, and marketing
http://generalassemb.ly/education/
Lynda
Training courses about programming, development, and creative
http://www.lynda.com/

Scientific

MIT
MIT offer a range of training courses and lectures on-line completely free of charge
http://ocw.mit.edu/index.htm
ABPI Learning Resource
A resource for learning the ABPI code
http://www.pmcpa.org.uk/training/documents/elearning/player.html
Biomed Search
Search for biomedically indexed images
http://www.biomed-search.com/
Crossref Search
Citation Finder. Great for finding the original reference location with little information input
http://www.crossref.org/guestquery/

Social

Reddit
The social news alert system that provides bonus commentary
http://www.reddit.com/

Search Engines

Kayak
Awesome site for when you're planning a trip
http://www.kayak.com/
Pipl
Looking up people based on user-name, name, email, or phone
http://www.pipl.com
Google Torrent Finder
Torrent Google Google torrent search 
http://www.google.com/cse?cx=003849996876419856805:erhhdbygrma&ie=UTF-8&q=&sa=Search
OV Guide
Search engine for movies and TV shows
www.ovguide.com