It was bound to happen sooner or later, and ATI has done it. The FireGL V7300 and V7350 will be the first retail workstation boards available with a massive 1GB of video RAM (with 512MB versions available as well), including 1GB frame buffer support. Not designed for games, they are designed to have immense acceleration for use in things like CAD. They are based on a 90nm process and a 512bit memory bus, and native support for huge resolutions. In the press release, this was stated:

"ATI's new ultra high-end workstation graphics accelerators leverage our best technology while focusing on the unique features of the workstation market. ATI has coupled increased visual fidelity with the power to drive extremely large data sets with the release of the workstation industry's first 1GB board," said Dinesh Sharma, Director, Workstation Products, ATI. "Just as we have captured leadership market share in the entry-level segment by targeted the specific needs of those customers, ATI has designed its ultra-high end boards to set the standard for the high-end of the market."
These cards step into the market at $1599 and $1999, making them some of the most expensive cards out there (though FireGL is known for being steep). Read the full press release for more info.