BUT none side by side like the Segway-

Two wheels in line - Schilovski Gyrocar aka Wolseley Gyrocar (built 1912)

        http://www.dself.demon.co.uk/gyrocars/schilovs.htm


Page on 1 & 2 wheel gyro stabilised vehicles including one built in the USA
in the 1960's

        http://www.dself.demon.co.uk/gyrocars/gyrocar.htm


GYROVER - Single wheeled gyro stabilised prototype vehicle


http://www-2.cs.cmu.edu/afs/cs/project/space/www/gyrover/gyrover.html


Modern French microprocessor controlled 2 wheel tandem version - seeking
startup capital
Rather suspect photos

            http://www.sardou.net/gyrocar.htm

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