Long distance codes and numbers:
http://www.timeanddate.com/worldclock/dialing.html

Making a site findable:
http://www.masternewmedia.org/how-to-make-my-site-findable-and-visible-inside-google-serps/

Online collaboration tools from Robin Good
http://www.mindmeister.com/12213323

Plan meetings across time zones:
http://www.timeanddate.com/worldclock/

Schedule events:
http://doodle.com/main.html

Shorten URLs:
http://www.tiny.cc/

Useful tools for learning:
http://c4lpt.co.uk/recommended/top100-2010.html

And we all need a chuckle:
http://xkcd.com/256/