You can change the color of the worksheet background by modifying the registry.  RGB values can be written to:

HKEY_CURRENT_USER\Control Panel\Colors\

"Window" is the value that corresponds to the worksheet background.  I changed all of the white ones (255 255 255) to something softer.  It affects all of Windows, but I didn't want glaring white in the other applications either.  A log out / log in is required for the changes to take effect.