November 7th is Carl Sagan Day (on what would have been his 77th birthday). Fun fact: our birthdays are three days apart. This tradition (or rather periodicity) was started by the Fort Lauderdale branch of the CFI (Center for Inquiry) several years ago. It has since become a nationwide event sponsored by the CFI. As Carl Sagan might say, be there or be superstitious.
It seems there is a "cult of Sagan" brewing. I'm looking forward to the upcoming remake of "Cosmos" involving Seth MacFarlane and Neil DeGrasse Tyson (supposedly arriving on our planet in 2013). Next up, Richard Feynman day (May 11).
Below are several printable poster (.pdf format) announcing the event: