TTL homebrew CPUs

I've been thinking more and more this last week about designing a CPU to be built from TTL logic ICs, purely as an interesting exercise. I'm thinking of a microprogrammed design with a pretty minimal register count - but as speed is never going to be a defining aspect anyway using commodity TTL, I'm thinking of going for a bit-serial ALU to keep the parts count down. Keeping the raw components pretty basic is another desired goal - no custom off-the-shelf ALU chips, gate arrays etc. Questions: have any others on here done stuff like this, or have any pointers to good resources? I'm learning as I go along here, flicking through technical manuals for 8-bit CPUs etc. and gleaning what I can from the web. MAGIC-1 is about the most comprehensive online resource I've found so far, but I believe it's a pure parallel core, and plus it's *way* more feature-rich that what I'm aiming for. I'm not interested in running UNIX-a-like software, or giving it hard drive interfaces or network stacks - I just think it'd perhaps be fun to design and later build something from scratch to do basic computation.