This one goes out to the web developers in the audience. In just about 40 seconds (if the site isn't already indexed), you can find out everything you've ever wanted to know about a website.

Whether it's traffic data, how many bookmarks they have collected all the way down to the names (and sometimes job titles) of the site's employees. It's all at your finger-tips with Quarkbase.

This is a stunningly simple and rich research tool for anyone who spends any time in web marketing. The only thing I wish they would add is a way to easily compare (column by column) multiple sites.

Quarkbase is a free tool to find complete information about a website.

It is a mashup of over 30 data sources and many algorithms gathering information from Internet on various topics like social popularity, traffic, associated people, etc.