My fave new (well, new to me) social software is StumbleUpon
See what the BBC says...
"StumbleUpon is a brilliant
downloadable toolbar that beds
into your browser and gives you
the chance to surf through thousands
of excellent pages that have been
stumbled upon by other web-users"
I have found sites I am sure I would never have found any other way!
Download that toolbar and... Start Stumbling!!