StumbleUpon is fantastic!
How can I ever get bored now when I have a few minutes to rove the net! Forget about "googling" the web and thinking up keywords to search for!
When I signed up to StumbleUpon (free, quick and easy) I simply considered a whole lot of options/topics and checked those that best applied and interested me.
I also downloaded the add-on for Firefox and now have a tiny button underneath my navigation toolbar that will transport me to a random site that suits my preferences and interests.
So, now whenever I have a few minutes to browse, I'll be surfing through this, seeing what interesting things come my way... I'll post the good ones to my del.icio.us.