\r\nThe granddaddy of all compact mopeds must be the Excelsior Welbike. \r\nThis British single-seat machine was devised during WWII at Station IX for use by the Special Operations Executive, and is the smallest motorcycle ever used by British Armed Forces. \r\n\r\nBetween 1942 and 1943 nearly 3,700 units were built and many saw action with the 6th Airborne Division at Arnhem during Operation Market Garden. They were dropped with the paratroopers in special impact resistant canisters and could be assembled and started in just 15 seconds. Powered by a Villiers 98cc single-cylinder two-stroke engine, a fully fuelled Welbike could cover a respectable 90 miles at 30mph. However, many of these little bikes tended to go AWOL as soon as they were delivered to the RAF as the fly-boys found them handy for pottering around the airfields. \r\n\r\nWith no front brake, lights or horn these highly collectable war relics are not strictly road legal, but could still be useful on a cross-country mission to recover your ratty ex-MOD Defender from a rural Free House car park. Roughly 300 Welbikes are thought to have survived; if you want your own hand-built replica, fabricated by craftsmen at the modern-day Welbike Company, it will cost you around £4,500.