There are quite a few popular cards out there - some of them are worth quite a bit of money - but look butt-ugly. For example, I have always found the 1938 Goudey Dimaggio to be an ugly card. Now I love what Goudey did with this set by putting a player's head on a tiny cartoon body. Doing that was pretty creative, but why on earth did they have to choose that specific face shot of Joe for this set? Take a look at it below:
That's how I look like when I'm on the toilet seat.
Now I could post a few more examples, but I want everyone on here to participate. So go ahead and tell us which card you find very ugly, but nevertheless is a very popular one among collectors. Oh, and it doesn't have to be baseball either (football, hockey, boxing, etc. is fine).