If you use Windows 7, try those:
Press and hold the Ctrl + Alt keys, then press the up arrow key.
Using the down arrow will flip it down again.
Maybe you accidentaly entered that key combo... or someone played a prank on you.
OR
Right-click on the desktop, select "Screen resolution," then, in the dropbox next to the "Orientation" label, select "Landscape."
Right now, it's "Landscape (flipped)"
Electro, November 2011
