Spotted these recently and thought they looked good:

  • AirGradient - "We design professional, accurate and long-lasting air quality monitors that are open-source and open-hardware so that you have full control on how you want to use the monitor."

  • Meshtastic - long-range, low-power, low-bandwidth, off-grid, decentralised mesh networks, based on LoRa radios.

  • Plausible - an alternative to Google Analytics - "Plausible is intuitive, lightweight and open source web analytics. No cookies and fully compliant with GDPR, CCPA and PECR. Made and hosted in the EU, powered by European-owned cloud infrastructure"