Your dissertation topic is probably more humorous than you thought. Or at least it is when you reduce your years of hard work into one brief sentence everyone can understand.
For a little levity and brevity you might want to check out lolmythesis.com, the dissertation humor site.
Created by Angela Frankel (angelafrankel.com), a senior at Harvard University, her site is a place for thesis writers to sum up their "years of work in one sentence" with mostly humorous, or sad, results (depending on your level of cynicism).
Here are two recent one line summaries to give you the flavor of the submissions:
"Pain is hard to talk about; poetry, masochism, and opium help."
"19th century Western libraries stole a bunch of shit from other countries and put it in display cases."
For more about Angela and her site, check out the Slate article "College Students' Thesis Topics Are Hilarious, Depressing" by Will Oremus.