Pavarotti on Google

[Lethevich]

You can try right-clicking on the image and looking at the properties and seeing what the picture's url is.  For example, today's is http://www.google.com/logos/pavarotti.gif

You can also leave the mouse cursor over the image for an alt-text popup to say what it represents (if the browser being used supports that) - and generally the changed Google logos will be clickable too, leading to a Google search regarding the event in question...

[Renfield]

[...] and generally the changed Google logos will be clickable too, leading to a Google search regarding the event in question...

Somewhat expected, from Google. But still a nice touch!