I'm assuming that the vapor pressure of a solid, like a liquid, increases with increasing temperature and decreasing strength of intermolecular forces.
I'm pleased with these two factors. We might refine the "intermolecular force" a bit - but not too much because apparently it's not well-established knowledge in 2016 - by distinguishing some sort of mean force, or force at a random relatve orientation, which acts in the liquid state mainly, from a kind of "best possible force" which acts ina solid, where the molecule are (often) arranged in nearly the best possible pattern.
Also, the symmetry of the molecules (provided the solid consists of many small molecules - that's not the case in iron, quartz...) is very important. Cubane solidifies very easily but its intermolecular force isn't much stronger than for other C
8 compounds. Same story for 2,2,3,3-tetramethylbutane or for benzene.
Then, you have the deformation possibilities of the molecule that favours the liquid and the gas over the solid. A cage molecule like adamantane favours the solid.
This all (there may well be other factors) influences the solid's vapour pressure, which can exceed 1atm for some compounds.