Celebrated indie brain-melter SpaceChem has been updated on PC to include a sandbox mode, and has given itself a price drop to boot.

The game's brainy developer Zachtronics Industries has permanently cut the price of the game to £6.99 from £8.99. Now you can sit there and get confused for hours on end with less of a fiscal outlay.

Sandbox mode has been designed to "facilitate 'experimental' pipelines, such as molecular computers," according to the update's patch notes. I had a look and it's expectedly complicated. This slots in to the game's ResearchNet area, which already allows users to create their own puzzles and submit them for consideration to be included in the game.

Permanent site licenses for SpaceChem are also being offered for free to schools until January 2012.

"As a solid entertainment title that also ties into real-world science and engineering, SpaceChem is unique because it is educational without falling into the trap of other "educational games" that often forget to be fun," said the SpaceChem website.

SpaceChem Mobile is also available on the iPad for £3.99.

SpaceChem is easily one of my favourite games of 2011. Just so you know.