Nice question! I'm looking forward to the answers here. Meanwhile, you could have a look at my TicTacToe game: https://github.com/Borkdude/tictactoe It's not large, and I'm not claiming high quality either, but it might be educational to read and poke at as a beginner.

It's a very simple game built as a webapp in the very simple Noir framework (webnoir.org). It also contains unit tests. It uses leiningen as a build tool (so you can simply run it using "lein run" or poke at using "lein repl", run the unit tests using "lein test" etc). As a next exercise I want to build it in ClojureScript (client side only), which should not be too hard.