I used something simpler for 20€ for a while to indicate my busy status: https://www.getdigital.de/pages/offlineprodukt/usb-mail-melder https://www.getdigital.d

I used something simpler for 20€ for a while to indicate my busy status: https://www.getdigital.de/pages/offlineprodukt/usb-mail-melder https://www.getdigital.de/pages/offlineprodukt/usb-mail-meld... I guess it‘s no longer for sale. It even worked with Linux. I wrote some shell scripts back then to indicate my busy status from my jabber account using this gadget.