Promoted on television and in various magazines in 1991, this 1-900 phone line contest promised winners would receive the grand prize, which was the Wyld Stallyns van from the movie, or two electric guitars signed by Alex Winter and Keanu Reeves as seen in the snap taken from the commercial above.  Runners up would receive a Nintendo Bill & Ted game cartridge or some Bill & Ted trading cards.  Players were asked to answer questions via their touch tone phones to win.
(And just in case we actually have to point this out, the contest is long over, so don't try calling the 900-numbers, babes and dudes!)