I am currently working on a project with eight foot ceilings, which can be very claustrophobic. It is the norm for most American mid/highrises and single family homes. The first misconception is that you cannot use color for fear of making the room feel even more closed in. You can definitely use color but paint the ceiling the same color as the walls. Try to stick with soft colors. This will make the transition from wall to ceiling virtually disappear.
Large-scale wallpaper & vertical stripes are other options.
Hang drapes all the way at the ceiling to elongate the windows.
Here is a gratuitous photo of the Delano drapes
(only because this client and I enjoyed them so much while in Miami
working on his condo there)
Lay a bold rug on the floor to pull the eye down, away from the ceiling.
Modern furniture looks great with low ceilings because it is commonly designed with a low profile. Leaving space open is also a good way to open up the room. Try to stick with only the necessary pieces.
Another gratuitous photo, this time from Mad Men
where the low ceiling is celebrated!