Using XeTeX there are many working files that get created in process of producing the pdf, and they litter the directory where my main .tex file is. Is it possible to change the working directory of XeTeX so that it stores all these scratch files in some other directory, out of the way?

There is a previous question on Superuser.com that discusses a utility that cleans up the working files by deleting them after they're produced: http://superuser.com/questions/95712/how-to-avoid-littering-ones-tex-directories-with-intermediate-files

That solution doesn't work for me since I'm using XeTeX, but also it seems like it would be preferable to simply be able to designate a "scratch" directory where all working files are saved. I haven't been able to find any info on how to do it though. Is there a way?

(My question is prompted partly because of the fact that I often work with files in a directory that is shared using DropBox, so it creates a lot of unnecessary traffic if files are getting created and destroyed willy nilly. I don't know if it affects speed in any way, but the idea of having a separate working directory that is not shared/replicated by DropBox would be a cleaner solution, even if I could use the method suggested in the earlier thread.)