Richard Woods Strike 20 trimaran design is trailerable, folding and intended for racing use. It does have a comfortable cockpit so would still be suitable as a daysailor. It uses donor hulls and rig from an F18 catamaran. There are more details on his website here:
http://www.sailingcatamarans.com/index.php/designs/27-trimarans-under-25/433-strike-20
Also a video of one of the first boats launched that was built to the plans.