There's a very nice library called ccxt that uses a code generator to produce python (async and standard), javascript, and PHP libraries that implement a standard interface for dozens (hundreds?) of crypto exchanges. I think a nice project would be an in-browser JS app that accessed each of the APIs in my exchanges (via logged in cookies or API keys or whatever) to pull trade history, deduct fees, and create a CPA-friendly tax form from all of my crypto exchanges.