Businesses can save millions of dollars by making suppliers bid for tenders using online auction systems, according to Sun Microsystems' chief executive Scott McNealy.

Speaking at the fifth annual JavaOne Conference in San Francisco, McNealy said all companies should use online trading exchanges to source suppliers. He also plugged iPlanet's Marketmaker private auction platform, which is scheduled for release this autumn.

The internet will become the "biggest stock market we've ever seen", said McNealy, adding that Sun is working hard to take advantage of it. "It's real-time ecommerce and it is here now. You ain't seen nothing yet!"

Sun has run experimental auctions, asking its suppliers to bid for purchasing orders, at established auction sites eBay and Mercata. McNealy claims that using the auctions has saved Sun millions of dollars because it can more accurately forecast outgoings.