The laws of gravity are a little more flexible in the desert
I created myself a very sophisticated, custom-made sand proofing for my d700 before taking it to the dunes. it involved a semi-transparent plastic bag and a hair elastic.
caused all sorts of problems such as somehow accidentally switching my modes to live view, but being too bright out to see anything on the screen, and freaking out when I heard the mirror flip up, but not close. thought I broke it and was going to have to send it back to nikon. Was also excessively difficult to focus, because I couldn't actually see much through the viewfinder, just had to point in the general direction, focus at something and hope for the best. I also ended up with several shots with the plastic bag blocking most of the view....pretty awesome stuff ;)
BUT... no sand in the camera. :D