Best book on sacrifice?

I wonder if anyone has a great book on chess sacrifice?

I don't know what the best book on sacrifice is, but The Art of the Sacrifice in Chess by Rudolf Spielmann is a classic.  I have that one but haven't worked through it yet.

A few more to consider are:

How to Become a Deadly Chess Tactician by David LeMoir http://www.gambitbooks.com/books/tactician.html

Essential Chess Sacrifices by David LeMoir http://www.gambitbooks.com/books/essentialsac.html

(there are pdf samples of the LeMoir books if you're interested in seeing what they're like)

Pawn Sacrifice! by Timothy Taylor http://www.everymanchess.com/chess/books/Pawn_Sacrifice!%3A_Winning_at_chess_the_adventurous_way

If I didn't already have more chess books than I'll possibly be able to read in this lifetime, I'd probably buy some of those.  My own playing is too materialistic, and it's a hard habit for me to break.