If you run WordPress, you may find out the hard way what timthumb.php is…
This was/is a vulerable zero-day exploitable file that is right now sitting on probably thousands, or even hundreds of thousands of websites…
This is going to wreck havoc across the web.
If you are using a wordpress theme other than a default there, run right now to find out if you are using timthumb, it might be timthumb.php or thumb.php, if you do, I suggest you delete it NOW, and then go find the updated version.
http://timthumb.googlecode.com/svn/trunk/timthumb.php
Just look at the google trend for timthumb and the trend for timthumb.php