Thanks. I'm actually very interested in lexing and parsing, because that's probably 99% of the stuff a layman-programmer gets to do with compiler theory in job. I mean not everyone gets chance to write the backend part, but parsing skill is almost used universally.
A fun exercise is writing a lexer generator or a parser generator. It's probably easier starting out with writing a lexer generator like Flex for your favourite language. I recommend using the Flex input format, than you can test your creation using Flex as a testing oracle! This is not something you can do in a weekend.
