Did you do a Google search the past few days? Did you notice this Google logo for St Patrick's Day?
Google has a variety of logos commemorating holidays and events. They've put them in this online museum for your amusement. However, we've been advised not to use them elsewhere. And if you would like to include a link to Google on your site, to please use one of their official logo stickers.
Here are more logos for St Patrick's Day.
This one is for last year, 2007:
This for 2006:
And a couple more for 2008 holidays:
For cuter logos, you can visit Google's online museum.