Today is Veteran's Day in the United States and some of the search engines have logos up for the special day. We have logos from Google, Bing, Ask all have special logos for the day - but not Yahoo. Yahoo didn't have a logo either the previous years.
It is also Armistice Day in the UK and Google has a red poppy icon and Ask also has lots of red poppies on their UK site, as does Bing.
Veteran's Day Logos 2010:
Search Engine Roundtable:
Armistice Day 2010:
I should add that there is a ton of complaints about Google now having a Marine Corps Birthday logo yesterday on their 235th birthday. You can see some of the many threads on that over at the Google Web Search Help forums and Google Webmaster Help forums.