Variation of the dutch rudder
, in which 3 or more people link arms while each man in the group holds on to his own penis. Everyone in the chain then moves their arms up and down, causing each man's hand to stroke his penis under other people's control.
"Hey, how was the orgy last night?"
"Kinda slow at first, but then someone suggested we start a dutch longboat, and that got everyone loosened up."