Google have recently released Google History which documents all of your browsing through a browser plugin. It lists all of your past searches and displays trends of your browsing. It has features for Bookmarking.
Looks like it could be pretty useful. I was about to comment on the fact that it would be more difficult to clear your history if your mum was wanting to see what you've been upto, but it's stored in your google account under the safe protection of your password - so that's pretty cool too.
Check it at http://www.google.com/history