I stumbled across Proteus by Twisted Tree Games recently and I've been exploring its charms over the last few evenings.
Billed as an "audiovisual wilderness exploration game", the player tramps across a colourful undulating landscape discovering strange musical features.
You can follow rain clouds, run along beaches, get lost in deep forests and climb snow-topped mountains - or you can simply stand still and let the ambiance wash over you.
The musical theme is central to the experience and the way sounds mix and merge together as day turns to night is beautiful and relaxing.
The landscape doesn't hold many visual treats but there are some interesting things to find as you wander around.
Strange standing stones draw motes of light towards them, changing the time of day as the player approaches, while gatherings of small white creatures honk out tunes, clamming up and disappearing if you get too close.
Proteus is still in its alpha stage but is still well worth checking out. It's especially atmospheric to play late at night with headphones on. You can download it from the official website HERE.