This isn't the overpriced Alienware package either!!!
http://www.hardwareanalysis.com/content/article/1728/
Once 3rd party board manufacturers get PCI-E boards out this should be a viable option! SLI IS BACK.
http://www.hardwareanalysis.com/content/article/1728/
On early driver revisions which only offered non-optimized dynamic load-balancing algorithms their SLI configuration performed 77% faster than a single graphics card. However Nvidia has told us that prospective performance numbers should show a performance increase closer to 90% over that of a single graphics card. There are a few things that need to be taken into account however when you're considering buying an SLI configuration. First off you'll need a workstation motherboard featuring two PCI-E-x16 slots which will also use the more expensive Intel Xeon processors. Secondly you'll need two identical, same brand and type, PCI-E GeForce 6800 graphics cards. For workstation users it is also a nice extra that with a SLI configuration a total of four monitors can be driven off of the respective DVI outputs on the graphics cards, a feature we'll undoubtedly see pitched as a major feature for the Quadro version of the GeForce 6800 series SLI configuration.
Once 3rd party board manufacturers get PCI-E boards out this should be a viable option! SLI IS BACK.