It's a good exercise, and one of those experiences that helps to take the magic out of things (which for many people is an intimidating barrier preventing further understanding and growth). Like writing a compiler, various network protocols, file parsers, operating system, or directly writing assembler (especially if you've always used higher level languages before).
For what it's worth, I found the emulator way easier than the codegen step for the compiler, and it's probably easier than the AST generation too. Can't say enough good things about banging out a crappy emulator sometime when you're bored. It's not a huge commitment!
