So this is an evolution of my 1x1 GR model that just held the display, as I wanted to have a double-sized unit as a temperature and humidity sensor. This uses my ribbed casing design, that has 2 heights at which panels can be slotted in. The lower panel in this case holds a RPi picoW - and so makes this a generic unit that can be used for any RPi Pico W project you wish. 

The top panel holds a AM2302 temperature sensor, and an SSD1306 OLED display, along with a USB-C socket for power. 

I programmed this to connect to my wifi, synchronise time, take measurements, show them on screen, and then upload those measurements to my MQTT broker (to be ingested into Home Assistant) - so this now makes a very versatile smart home unit. If anyone is interested in the source code (micropython) I used for this - say in the comments, and I'll get it on a GitHub repo. 

I added a blank panel into the print pack here (2x1), as I suspect that'll be of use to anyone who wants to modify this for something else. 

Enjoy folks- I look forward to seeing more builds and evolutions on this design. 

Jimlee

p.s. Kudos to Grizzie for the great Gridfinity Refined variant, and of course Zack Freedman for the original Gridfinity. 

Subcomponent stuff: 

The SSD1306 OLED is everywhere.. this is the amazon prime version - https://amzn.to/40DPIde - but also available via lots of other places if next-day isn't the top priority. 

These are the magnets I use for all my gridfinity stuff: https://amzn.to/3DFTKtO.  

The wider electronics in the photo are part of a kit I bought for the Raspberry Pi Pico - which I would recommend - it comes with the breadboard, pico, power supply, jumper wires, LCD and a whole range of other bits to prototype some nice projects. https://amzn.to/4gSPci6

(Note: These are associate links, which means that they don't cost you any more, but I get a small cut if you purchase via these links. This isn't a big money-spinner, but I find it so useful to have sub-components linked in models that I download - so I know I'm getting exactly the right bits without much research, and it helps support my tinkering!).