Per the recommendation of Scott Hanselman, I am using MaxiVista for using my Laptop as a second (and third) monitor on my desktop system. Right now, they are looking to release a new version, so they have discounted the current version by 30%. Or you can wait for the next release (which will be 50% off for upgrades--so the price is close to the same either way--you just get to start using it today).
