The other day I happened upon the Firefox Add-On page and decided to give the recommended Add-On a try. I’ve been infatuated ever since.
Though there’s an inordinate number of buttons on the default toolbar layout, StumbleUpon is pretty simple: You/others browse the web and when you find something you like you give it a thumbs-up 
or a thumbs-down 
if you don’t. Then there’s the magic button 
which randomly picks pages from the submitted pages that are recommended (thumbs-up). Their pitch says it pretty well…“Channel surf the internet.”
I warn you, it is very addictive, but if you choose topics you are actually interested in, you’ll find quite a few cool and relevant sites. Check out my recommended sites so far..