A group of indie developers who have a knack for putting computers in the strangest of places have built what they are calling "Doom Piano" -- a piano that, well, plays Doom essentially. The piano, being presented to the public today at the Virgin Media Game Space in London, has been put together by a group of industry veterans including VMGS organizer David Hayward, Polish dev Sos Sosowski, Die Gute Fabrik's George Buckenham and Honeyslug's Ricky Haggett. Hayward explained on Twitter that they used a combination of copper tape and I-PAC keyboard encoders to allow the keys of the piano to interact with the computer inside, while a screen on the front of the piano displays the Doom action. Each of the white keys represents a certain action, such as movement left and right, while the black keys are all used for shooting. One key in particular, which is partially broken and makes a thud noise when hit, can be used to open doors and throw switches. Building game machines inside strange and wonderful objects has become a passion for a growing number of indie devs in recent months. At GDC Europe there were plenty of strange machines to play around with, including an arcade machine inside a suitcase.