Dual Monitors with MacBook Pro
DisplayLink
DisplayLink makes USB graphics adapters for PCs and Macs. You can add as many displays as you have USB ports and processing power.
You would use the built in graphics card for one of your displays and use the USB graphics adapter for the other side. I would suggest using your three displays in the following order:

Primary: MacBook Pro built in display

Secondary: Display connected to Mini DisplayPort

Tertiary: Display connected to USB graphics adapter.


The USB graphics adapter solution is fantastic, but it can be a little slow sometimes.