Today is Memorial Day in the United States and we have logos from Google, Bing, Ask.com, Dogpile and others. But one big 'search' player that is missing a logo is Yahoo. Normally Yahoo does have a special logo for the day but not today, not currently.
You can see Yahoo and the other search engines logos for the past years on Memorial Day for 2010, 2009, 2008, 2007, 2005 and 2004.
Google was actually the one who rarely posted anything for Memorial Day. The first year they did was with a yellow ribbon in 2009 because they do not post logos for sad days.
In any event, here are the logos, themes and ribbons from the search industry.
Forum discussion at Google Web Search Help.