Disable keyboard and mouse with kid key lock
With Kid-Key-Lock you can prevent toddlers from accidentally pressing unwanted buttons on your keyboard and mouse, but you can also disable your keyboard and mouse to clean them.
Kid-Key-Lock seats on tray for easy access and it can be set up also with a shortcut key. Note that It is not totally reliable, sometimes, after persisting use, keys escape their lock.
Here is what I do: pressing the WinKey + L I log off and the keyboard is instantly locked, without using any other software. Just remember your password to log in again!
Note also, that if you are listening to music, it keeps playing while you are logged off (although you can not change the volume of course).