Excellent article on Simple Top-Down Parsing in Python. The nud and led business could be better explained, but the rest of the article and code is great. I learned several things I hope to employ shortly.
I'm trying to remember if we studied this in compiler class or not. I think not, although I have terrible memory, so it's possible we did.
Anyway, a companion tutorial article that would approach this strictly from the perspective of using the toolkit Effbot built in his article would be nice. In other words, knowing the under-the-hood details is fantastic and informative, but given the tools and helper functions built in the article one could fairly easily build a parser without worrying about how the helper functions are implemented. Sort of a user manual for building parsers given the helper functions.