This is kinda super niche, but here we go. Some of the seedlings in the greenhouse are "leggy", which means for whatever reason, normally lack of sun, they grow taller than they should (searching for sunlight) and don't really have the strength to support themselves properly. Most likely because the greenhouse is warm; "yay we can grow it's Spring", but also winter "hey wait, where's the sunlight?"
With the larger plants I have proper wooden stakes they can grow up. But these seedlings are still super small, so I need something that's a) tiny and b) can keep them upright.
I did have a look around for something I could use, but nothing was quite right, so of course I ended up 3d modelling exactly what I need. Tomorrow I'll take them down to the bottom of the garden to try out and print some more on Wednesday.
fwiw: as annoying as using plastic is, and PLA isn't the worst, these will be reused many many times, and eventually recycled at an industrial recycling plant. Also, more importantly it's pretty neutral in the soil, unlike the tiny wooden "stakes" I've used which have ended up growing mold and and fungus.