I've only played through a few levels so far but I can tell that I'm going to get sucked into a vortex of lost time with The End - a new game from Channel 4 and Preloaded. Granted, the official description says:

It is a game of self-discovery for 14-19 year olds which integrates strategy, puzzles and philosophical questions into a world which explores a range of commonly (or less commonly) held views about death, belief and science.

And I'm a 32 year old.. a bit outside the range of the intended audience but that's not going to stop me. It's got great game mechanics, phenomenal illustration style and, pleasantly enough, some thoughtful aspects as well.