Many external flashes have a reflector that can be turned up, some, like the Nikon SB-600/800 can also be turned sideways so that you always have a chance to bounce the flash against a suitably surface up or to the sides, regardless of you shooting landscape or portrait.
The SB600/800 can also be used as a slave to the built-in flash so that you get a nice crossfire.
Have a look here: http://www.cameralabs.com/forum/viewtopic.php?t=1021
To keep the Camera Labs forum tidy and well arranged, I have locked this thread.
Please continue at thread #1021 above.
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