An anonymous buyer at a Sotheby's auction in Melbourne has paid $84,000 for a digital installation work showing a man skateboarding at Bondi.The DVD by artist Shaun Gladwell, Storm Sequence, 2000 was the first installation of its kind to be auctioned in Australia.It shows Gladwell in slow motion sequences on his skateboard, with a stormy Bondi landscape as a backdrop.It was expected to fetch between $70,000 and $90,000.Earlier, Georgina Pemberton from Sotheby's said the auction was part of a new global trend in contemporary art and art dealers and collectors would watch closely to see how it performed.Also at Sotheby's, a private Melbourne collector paid a record $1.86 million for the Eugene von Guerard landscape painting entitled The Great Lake, Tasmania.