There are a ton of bad card designs out there. Green borders on the 2001 Topps set, yellow on the 1991 Fleer set. Poor photography on the early Donruss and Fleer sets. The Metal Universe cards are a level of bad unto themselves. That's just a few examples.
One of the top bad designs has got to be the 1995 Fleer design. Here we see Jose Canseco on card number 281 as an example. As you can see from the picture, there just aren't any redeeming qualities about this design. The split frame, overly busy front, and psychedelic colors drive me batty. Looking at the team set in binder pages is about enough to cause a fit. Anyone attempting the whole set should be carefully monitored for signs of breakdown.
What's the top worst design ever in your opinion?