cervesaebraciator writes: The 2.5 tonne Harwell Dekatron Computer has now been restored to working order and is on display at the National Museum of Computing in Buckinghamshire. The Harwell Dekatron was made in 1949 and used by the UK's Atomic Energy Research Establishment. In its heyday, the Harwell Dekatron would work away for up to 80 hours per week, notably doing computations in decimal rather than the binary we are now accustomed to. A multiplication performed by this computer would take from about five to ten seconds. The computer was found in storage and restored to working condition, the majority of its 480 relays and 828 Dekatron tubes still original. The main article includes a video where, unlike a modern computer, you can literally see the computer store data and perform calculations.