I noticed that the [url=http://www.adobe.com/products/acrobat/readstep2.html]latest version of Adobe Acrobat Reader[/url] contains an ad button in the toolbars which has no obvious means of disabling this from the user interface. To get rid of it, add in the following DWORD value in your registry:
HKEY_CURRENT_USER\Software\Adobe\Acrobat Reader\6.0\AdsInReader\bShowAds
set it to 0 and the button is no more! I found this solution on the web so I can't take full credit.
Regards,
Jeff