Invariably many bishop pieces seem to have a diagonal slot cut into the “head” area of the piece.
Is there a significance to this and if so what is it.
It’s a stylistic representation of the folds in a Bishop’s Miter, a fancy kind of hat.
Pix.
http://www.alltel.net/~frdaniel/eacc/images/miter.jpg
http://www.coloradodiocese.org/Programs/miter4.JPG
DDG, Fastest Google in the West.
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Here’s a question for the assembled Dopers: is it faster to do your own research on the 'net, or is it faster to post a question here, then wait for Duck Duck Goose to do the research for you? If the latter, how do you justify your pathalogical laziness?
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What am I? Chopped Liver? 
No, Evilhanz, but it would have been helpful if you had provided a link to a picture of chopped liver.
I always thought it was a poorly designed bottle opener. 
It’s a place to put the “be back in Five minutes” and “out to lunch” notes. 
Like NotBob13 said, it’s a card holder. Just like the rook is an ashtray.
– Dragonblink, who has seen a chess match where one of the players really did use his rook for an ash tray.
DDG IS the absolute queen of Google - has there been a ‘DDG’s Google tips’ thread maybe? - if not, can we have one?
What is that last one? Popey the Birthday Cardinal?
Shoot, I’m too lazy even to spell “pathological” correctly, so I guess I’ll continue to rely on DDG to do my research!