AV8R's Flight Sharing Board
This is for the aviator who wants to share costs, or wants company, and for the traveler who needs a quick lift in a light aircraft.

Hostels.com Ride Board
Global flavor. People looking for rides, riders and companions. All countries. About 200 entries at any one time.

San Diego - HIAYI Bulletin Board
A general board but it's active and there are quite a few postings for rides offered and rides wanted.

West Chester, PA Ride Board
A ride board in West Chester PA.

WWW Autostop
Italy only - for those interested in offering a lift and those looking for one. Written in Italian and English.