I'll start this year by strongly recommending a game I played in the 2011 Interactive Fiction competition. It's a dungeon combat game called Kerkeruip - it's a 'roguelike' if you know what that means. It's highly tactical and very addictive and challenging. I've played it at least 50 times. Each game last 5-45 minutes (mostly at the shorter end).

It is free to play. Just download the interpreter Gargoyle for your OS:

http://code.google.com/p/garglk/downloads/list

then download the Kerkerkruip 'Story File' itself from IFDB (other resources for the game are also linked on the right side of the page):

http://code.google.com/p/garglk/downloads/list

and drop the story file into Gargoyle.

Note - you definitely need to read the 3 page Beginner's Guide before you play. If you just go along spamming 'attack', you will be slapped down hard.

This is hardly a conventional text adventure game, but if you've never played any game like this before, there's also tute videos available where the author talks you through a game session.

I've cleared the game on Easy (wasn't all that easy) and Normal, but not Hard yet. The game also has its own achievements system.

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