It sounds like you would really have enjoyed SICP[1]. I remember feeling exactly what you're describing when I finished the Logo interpreter project. Logo, which (despite its dearth of parentheses) is a type of Lisp, is a surprisingly simple language which is not that far removed from lambda calculus.

[1]: http://mitpress.mit.edu/sicp/

If you have time on your hands in the near future, you should definitely give SICP a go--it really is a brilliant book.