Please vote! As you make your way to the polls today, Dan Gillmor posts a helpful guide to polling-place photography laws, from Stanford's cyberlaw clinic, so citizens with cameras can help document the state of the process.
If you don't know where your polling place is, the League of Women Voters' Vote411.org gives an interactive lookup, along with information about state-by-state ID requirements and election law. Demand a real (not provisional) ballot if you're entitled to one.
Finally, if you do encounter problems voting, call the Election Protection centers, 1-866-OUR-VOTE, where volunteers will be tracking and responding to problems, including those of electronic voting machines. I'll be listening in NY.