If you ever wanted a video card that rivaled your desktop for the amount of memory it has, Nvidia has just the ticket for you. The company has recently released their Quadro 5800 card, which comes stock with an impressive 4GB of memory and is supposed to have upwards of 102GB/s of memory bandwidth available to it.
The massive card is intended for ultra-powerful workstations that could actually justify such large amounts of RAM, like in the CAD and Engineering fields, and comes with an ultra-powerful price at around $1500. That gets you essentially a GT200-based card with massive amounts of RAM that consumes up to 189W of power when in use.
These pricey cards compete with AMD's FireGL line, and the introduction of a 4GB unit gives them a selling point AMD currently does not have.