Lately me and my friend Andreas Grech (http://blog.dreasgrech.com/) developed jointly a Microsoft XNA game in just under a sleepless and coffee ridden 24 hours called Typocalypse which is a game where you have to type the words under zombies before they reach you.
My involvement in the game was in using my previous two blog posts, the biasing function for gradually increasing the difficulty of the game by gradually biasing the randomly chosen words to prefer longer words as the score increases and the trie for determining which zombies have a word which has a prefix that matches the currently typed text. I was also responsible for handling keyboard events, displaying the words under the zombies and sound effects which I created orally.
To give credit where credit is due, the background music was taken from the Amiga game The Great Giana Sisters, the pictures including the background image where found from google images and we couldn't be bothered with looking for them again and the library which enabled capturing of keyboard input was taken from here which was developed by George Mamaladze.
The game is open source and you can download and use the source code if you wish, but keep in mind that this was developed in under 24 sleepless hours so at some point coding started getting messy.
Link to the game is http://code.google.com/p/typocalypse/downloads/list.