If your notebook computer is the type where the screen opens out flat, then you can use Turntamer without an additional monitor!
You simply start up Adobe PDF reader, rotate the image, then go to full screen. TurnTamer will step forward or backward through the pages! And there's more.... see below!
If another musician (vocalist) is performing with you, use a second monitor connected to the laptop above, and the vocalist's pages will turn automatically with yours!
Thanks for this idea to cybernator, Don Kinnier.