Yes, it is.
You have two choices.
1. Run Xinerama. Check the tutorial at:
http://tldp.org/HOWTO/Xinerama-HOWTO/
2. Run Nview using Nvidias official drivers. Check the Nvidia Drivers Readme for that.
http://www.nvidia.com
The both work just as well, though Xinerama is more widely accepted across different programs, and Nview isnt completly Xinerama compatable.