Relative value of chess pieces on queenside vs kingside I've read a few variations on the relative value of chess pieces ( Q=9, R=5, N=3, B=3, P=1 ), but I've yet to encounter a variation in value according to the side of the board the piece is on. With regard to rooks, bishops and knights, might there be a a different inherent value whether on kingside or queenside? For instance, I've always found a greater value to kingside bishops because of their inherent nature of attacking the opposing king's squares before and after castling.

Has anyone seen any documented systems based on this idea? I'm not looking for speculation.
I don't think that there's any value to where the pieces start, but the value of the pieces changes drastically depending on where they are on the board at a given time.  

For example, a white knight on d6 that can't be exchanged off is usually considered to be worth a rook.  Similarly, if black has castled kingside with pawns on f7, g6, and h7, and white has an unopposed dark square bishop, that bishop can be worth a rook (at least) if white can attack the black king.  

The only pieces that are inherently different are the bishops (one light, one dark), but they're still equal until the pawn structure has been determined.  A bishop is usually strong when the opponent's pawns are on its color (so they can be attacked) and the friendly pawns are on the opposite color (so they don't get in the way).