I have a 1991 Topps baseball Chris Hoiles, "White Inner Border" A pretty rare error as they were corrected early on.
I also have a 1991 Topps baseball Chris Hoiles, error with the wrong back. The back is 1990 Topps football Ferrell Edmunds Miami Dolphins. Not sure of the rarity of this one as I have not seen any others like it.
I also have many others from different sports, and manufactures.