One of my favorite things about football season is the signs that fans display in the stands. They range from awkward phrases that try to incorporate TV network names ("Cooking Brady Soup: We Want a SUPER BOWL Of It"), to misspelled knocks at opposing players (Eagles fans asking Randy Moss "Boxers or Breifs?") to inappropriate commentary on national tragedies:
My favorite is the "D-Fence sign". Usually it's a team effort - one fan holds up a cardboard D, while another holds a section of picket fence. Since the cancellation of Concentration, the D-fence sign is easily the most common example of the rebus in contemporary American society. And most of the time (and 100% of the time at Raiders games), you can assume the person holding it has no idea what a rebus is.
While D-Fence may have peaked in popularity, I can't endorse any of the spinoffs such as "Off-Fence" (generally with a cardboard light switch) and D-Fence inventor Big Lo's confusing pro-Seattle "Sea-Fence" sign. However, I do think "Sea-Fence" would infuriate Raider fans more than a regular D-Fence sign would, because it involves words, and Raider fans don't know how to read.