The worlds oldest computer - the Harwell/WITCH - designed and built by Harwell engineers and used for 7 years in the 1950s. It uses decatron valves for memory, so there will be plenty of flashing lights when it comes online. It was actually no faster at calculations than a human, but could keep going far longer (as well as not make mistakes). It's longest stint was over one Christmas and New Year where over a period of about ten days it was left to its own devices with miles of punched paper tape to work through and was still chuntering away when the workers returned from the holiday. At the end of its useful life a competition was held between colleges as to who could produce the best case for its future use, won by Wolverhampton and Staffordshire Technical College, and renamed by them WITCH (Wolverhampton Instrument for Teaching Computing from Harwell). Donated to Birmingham Science Museum in 1973 and displayed by them for many years, it went into the reserve collection on the closure of the original (and far better, in the opinion of many) museum, and loaned to its present custodians for restoration to working order in 2009.