Today is Father's day and the day is now over for me at 7:30pm ET, I am exhausted, I have a lot of young kids. :)
In any event, the search engines, at least some of them, have special logos and themes for the day. Google and Bing and even Dogpile have logos and themes. Ask.com, Yahoo and some others do not.
Here is Google's logo for the day:
Here is Bing's home page for the day:
This image has been removed because of fear of being sued over copyright...
And here is Dogpile's animated image for Father's Day:
Forum discussion at Google+.