Hacker's Delight builds upon HAKMEM, cataloguing all kinds of bit-twiddling tricks. It's not the kind of book you'll use every day*, but it's a great reference for your bookshelf.

http://www.hackersdelight.org/

If you do use it every day, I'd love to know where you work.

Hardly ever use it, but we have, for example, used the tricks to count the number of set bits found in Hacker's Delight :)

Alan Mycroft has given some C interpretations of HAKMEM examples at http://www.cl.cam.ac.uk/~am21/hakmemc.html.

This piece is quite charming: "If arithmetic overflow is a fatal error, some fascist pig with a read-only mind is trying to enforce machine independence." (Item 154)

Some of these are pretty hardcore...