I spent some time today building a package for the system. It's basically made of balsa wood, as it is easy to work with. But even with that, it's still looking quite bad, as I don't like "standard" do-it-yourself tasks :)
Anyway, I'm satisfied with the results, here is how it looks like :

Here is the contents : main board, SparkFun header board holding the LCD screen, keypad board, and some last-minute parts (I forgot to tie P0.14 high, and the power switch).

Next step, maybe paint it and, more important, make a game for it :)