Full feature custom PCB prototype service:https://www.pcbway.com/
One pcb board for free, for new pcb designers,try it.
nokia 5110 lcd display and dht11 to make temp and humidity gadget:
https://youtu.be/lpR8hmQY8JA
Arduino lcd 16x2 display and soil sensor to make watering system:
https://create.arduino.cc/projecthub/PatelDarshil/soil-moisture-sensor-with-lcd-display-71d6df
For DIY Led hourglass i got this info:https://www.reddit.com/r/arduino/comments/5uldig/arduino_hourglass_my_first_finished_project/
MQ9 gas sensor experiment video:https://youtu.be/MlNrHiFGRKo
ISD1820 Sound Voice Recording Playback Module Recorder:
https://ebay.to/2WecYxd
Did you miss our previous article...
https://coolstufftomake.com/gadgets/7-amazing-homemade-gadgets-that-will-blow-your-mind