When is Good is one of the most practical web tools I've found lately. Basically, it's a way to coordinate dates and times with a group of people. http://whenisgood.net/
From the website:
"An a easy online tool that can help you choose the time for your next meeting or event.
Just click the grid for all the times that are good for you - we send you a link to circulate to your participants. They see your proposed times and click on when they are free. You see the combined results. Simple.
- Eats time zone confusion - perfect for international conference calls
- Beautiful personalised URLs for each of your events
- You write the invitations - no cheesy automatic emails
- Free for basic usage
No sign-up form. No password to choose. No fuss at all."'What's your favorite web tool? Share yours in a comment below!