A very basic lisp interpreter targeting Scheme. Supports let, quote, atom, def, cond and lambda as special forms, and +, -, *, /, first, last, rest and cons as native functions.
Lisp code is interpreted by parsing it, constructing a tree of Node objects and then evaluating them from the inside out. It's a very naïve, rudimentary approach, but then the original implementation was written in a couple of hours on the train, so it doesn't aspire to greatness (or even usefulness).