The dream of SLI on a non-nVidia chipset has been the dream of many. It was finally realized for the Core i7 and Core i5 (X58 and P55) when nVidia and Intel came into a licensing agreement.
But that left everyone else on the Intel side of the market out in the cold unless they were lucky (or unlucky) enough to have a board with an NF200 bridge.
Well there is hope for all the others out there. It looks like someone over at Expreview found a way around this through software. They were able to use this software in Directory Services Restore Mode to enable SLI on both an X38 and a P45 chipset.
The details of the software have not been made public yet and there is an issue with enabling SLI in normal mode but according to Expreview these will be taken care of soon.