Alright, here are a few things I have messed with as recently.
Here is a little SIP container design I made in hopes of them helping how I run things in my veg/stasis tent (lol). 2 plants being tested in them at the moment 1 clone and 1 plant I did not know was an auto till it was a bit late, so when I realized what was going on I just threw it into one of these SIP pots. But I have geared up for switching over to mainly using these for some veging or little auto run.
I scaled the print down to 75% and 50% just for the hell of it, but the 50% is a no go and the 75% scale one will work but did not print as good as I would have hoped and I think its just from a scaling issue. Smallest one will turn into a decoration but the medium one may be fun to use.
Here is a link to @CrunchBerries thread where I have posted this and he also has lots of interesting info in this thread about how people use SIP containers. CrunchBerries’Probiotic SIP Thread - #52 by bassman5420
Older picture of a rough draft plant stake, words hit with a silver paint pen after done printing. They look a bit smoother with a few setting tweaks like ironing etc.
These are my pride and joy right here. My solution to my own growing problems/needs.
Tent spreader/trellis and wall support units. This set adds about 4"x4" to the tents canopy space.
Here is @BeagleZ using them in action for his 4x4 tent. BeagleZ Corner - #519 by BeagleZ
A quick tutorial video.
Desktop battery holder/organizer for mine and @Pluckyevil’s vape batteries
Only 1 thing needs said about this one…
OVERGROW THE WORLD!!!
I wont keep going on with this post, but there are all sorts of other things like 6in fan tent pole mounts, coin flip washers, various cord slips and organizers, plant training clips of various sizes and styles, etc etc etc.
Love 3d designing and printing 
Now I might be forced to design my own seed holder and scrap the printed washers I make. I had it on my list of things to design, but I guess its getting bumped closer to the top now heh.