long shelf life. reporter: for the past six years, doritos has been putting their fans to work making the ads. sweet heart, i would love to, but the guys are waiting for me. i ve got doritos. reporter: and then having them vote on which one makes the cut. this is going to be fun to vote and see their vote count. reporter: something other companies are catching on to. this year, audi shot three endings to this scene s prom experience. and is letting viewers vote online, selecting which one makes it to the big screen. budweiser is asking viewers to follow them on twitter to name this baby colt. their latest edition to their famous team of clydesdales. the biggest hail mary of all, though, goes to pepsi, who bought just one ad and is using the rest of their screen time letting fans strike a pose with a can as they introduce boeyonc for their halftime show.