Smalltalk-80: Bits of History, Words of Advice is one of my favorite books on language implementation. It's dated (the machines targeted were things like 8Mhz 68000 boxes) but details and pragmatics of bootstrapping your way into a working system from a tape dump are a fun read.
Especially the cartoon captioned something like "2+2=3.9erstėsdgdfg - the system is 99% working" - both funny and accurate, after a fashion :-) Too bad all we got for the MVC book was "The black art of MVC programming" :-(
