Just for fun here are a couple of applet based roguelikes I wrote a while back. The first is a reasonable example of a simple and concise roguelike. The second is an attempt at a roguelike with directional player facing, it also adds directional monsters, hearing and sprinting. The above-right picture shows an unknown monster sneaking up on the player from behind and an ant, above-right of the player, looking towards the player.
I hope these are somehow informative/fun for someone. The source code for both applets is public domain.