On: A Friendly Introduction to Assembly for High-Level Programmers

[bitexploder]

Or something like msp430, doing math on 16bit address space is fun and only 4 hex digits. All the concepts transfer.

[zellyn → bitexploder]

Working through the microcorruption.com challenges left me really liking msp430 assembly

[bitexploder → zellyn]

It is probably one of the best ways to learn how computers work :)