Cold reduces reciprocity failure, and is used particularly for astrophotography. See http://en.wikipedia.org/wiki/Photographic_hypersensitization#cite_note-15.

My own experience with Kodachrome (RIP) was that very cold weather reduced the blue-green cast of nighttime skies and cityscapes. Note that this could lead to frostbite, by the time the camera is cold enough to matter, and the camera should not be allowed to warm up where humidity can condense on or in it. See the following, from the above URL:

Webb, J. H. (1935). "The Effect of Temperature upon Reciprocity Law Failure in Photographic Exposure". Opt. Soc. Am. 25: 4.

Hoag, A. A. (1961). "Cooled Emulsion experiments". Publications of the Astronomical Society of the Pacific 73: 301.

BTW, a few posts here seem unfamiliar with reciprocity failure: for long exposures, e.g. a minute or longer, the film behaves as if it were less sensitive and therefore requires a longer-yet exposure. For color film, this is not uniform for each layer, and produces a noticeable color shift (e.g. sickly green for Ektachrome). Cold reduces this. What might be happening on a quantum level is that at higher temperatures, the excitation of the silver halide/sensitizer complex is lost before a reaction occurs.