How do I remove the KDE 4 Plasma Tool Box/cashew icon from the desktop?

You can delete the toolbox cashew widget this way:

1. Open a terminal and type: sudo -H dolphin or kdesudo dolphin enter your password

2. In dolphin, navigate to /usr/share/kde4/services

3. Search in this folder for plasma-toolbox, there should be 3 files named plasma-toolbox-(*something*).desktop

4. Make backups of these in another folder and delete the originals

5. log out and back in

Done, no more cashew :)

Install Py-Cashew -- it's an additional script that removes the thingy (it can also be downloaded via KDE widget download tool)

There are also Stealth Cashew that let's you configure cashew transparency.

I found another alternative, in case anyone's interested: the "Stealth Cashew" widget also lets you hide the cashew. It requires the 'plasma-scriptengine-ruby' package to work, though.