I'm reluctant to visibly switch off my mic during video meetings. That's why I have a keyboard shortcut mapped to the command amixer set Capture toggle, but XFCE doesn't have a straightforward way of displaying if my mic is muted or not. This is where togglemic comes into play! With a handy big button and an informative LED it shows me if my mic is hot or if I can hack away on my mechanical keyboard without disturbing other participants.

I won't lie, I threw this together rather quickly so portability was not on my mind. There is one major caveat:

This sketch uses the Keyboard library which requires a board with 32U4 or SAMD microcontroller. Getting a Nano, UNO or other type of microcontroller to work as a keyboard is also possible: See here for an example and here for another explanation.

There is also this very nice project which interfaces with PulseAudio through a client Python script running on the PC directly.

Of course you could also use a keyboard shortcut to visibly mute the mic in Zoom/Skype/etc. directly like here.