Adobe Acrobat Professional 7 on Windows XP is the worst offender. Given the nature of the product, it is reasonable to integrate with some other programs, and I am happy to be able to generate PDFs directly from Word. And the fact that they chose to offer that capability by adding a button to my Outlook toolbar is reasonable. However what is not reasonable is that there is no way to disable that feature. They configured their button to be always on, no matter what. When you try to configure the toolbar to remove the button, it is the only one greyed out - meaning that they think converting to PDF is more important than actually sending an email!
The reason I care so much is that because it is an always-on button, if you make the toolbar small (like I do to avoid having toolbars take over my screen), then it is the one that stays visible, and the buttons I actually want (Send and Accounts) disappear. The only solution I found is to edit the registry to disable the PDF plugin to Outlook. So Adobe has forced me to disable their product so it doesn't drive me crazy. Nice job Adobe - now I can be mad at you every single time I send an email.
The second offender is Apple. They nicely make it easy to offer an update to QuickTime and iTunes, but every time they update, they re-add buttons to my desktop and to my QuickLaunch bar. Do they really think that since I removed them the first time, I'll want them the second time? And do they really think that a minor security update should give them the opportunity to get in my face? Nice job Apple - now I can be mad at you too every time you offer me an update.
