It has been around for a while and cost a million yen, but the ファイヤートリックボブ (FAIYATORIKKUBOBU) was a beautiful looking jet-powered bike. I cannot figure out the specs from the crazy google translation, copied below the fold, but suspect it would make one fast commute!

Help run the engine, for aircraft equipped with TABINJETTOENJIN RAJIKON structured as a real jet. The smell and the sound of hot air, you can get real experience as real. Full-throttle state (turbine rpm: rotation per minute 120,003 thousand) thrust in the 5 km (4.4 equivalent of horsepower) to get HAIPAWAASHISUTO, continue to pull the pedal in the flat road, and before I knew it fast you can reach. Since there is no sense of acceleration torque but it is not (about to get a child back then), also helped KUREZU takeoff climb also.

found by @bpickard and Crunchgear
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jetbike photo

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