Billottti – U.S. Pat. App. No. 2004/0100791
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Wheaton – U.S. Pat. No. 6,209,147
US Pat. No. 6,210,728


US Pat. No. 6,368,227 - Swinging On A Swing
            US Pat. No. 6,293,874 - Butt Kicking
            US Pat. No. 5,960,411 - One Click

Sample Published PCT Application