O.Symetric “Harmonic” Chainrings
“Those chainrings are called Harmonic, and they offer a larger gear ratio when the crank is horizontal than when it is vertical (the opposite of Biopace). I asked Bobby Julich about them, and he referred me to the company’s website. And lest you think they are a revival of the old Biopace design, Julich says “they are the furthest thing from what Shimano had!”” Velonews Techtalk
They still didn’t help Vinokourov as Mick Rogers takes Gold in Verona for the 2004 UCI World Road TT champs: First Edition Cycling News for September 30, 2004
SuzyJ points out that these have been around for ages, see also:
where can i get a chain ring at 54 teeth or higher. they are great for hill climbing
you can get them at http://www.online-cycling.net/shop/