[weekendwarrior]

I like checkerboard on floors, but not on walls.

HOWEVER, if you did want to do checkerboard on a block wall, and were worried about the lines being crooked due to the un-even texture of the block, there is another option. I once saw a guy purchase peel and stick vinyl tiles from Lowe's, and put them on his wall. I think he said they were available in 12", and 16" or 18" squares, I forget. He bought black and whte tiles. and it turned out pretty nice. Of course, he was meticulous with making the seams all line up perfectly.