I'm sure many have this problem of, what do I buy for the person who has everything I can already afford? 'cause I have that problem now. My dad has gone deep into 3DPrinting in his retirement (he handed me down my Ender 3). He's got both an Ender 3 and a resin printer, tho I can't remember what model.
I was hoping to pick the hive mind for some useful 3D printing related ideas that won't break the bank. Some useful utilities that maybe I hadn't thought of. I'd really appreciate any help.
Spaghetti detective (obico) is a good gift idea. Also maybe a Raspberry Pi clone for Octoprint. I know Bigtreetech is selling an RPi clone for $45 that also has pinouts for Klipper.
Create a repository of models for him or design something for him if you have the skills! He may have the tech, but that other stuff always takes a lot of time.
Either start a large collection of models for him to make, or design him something he has always talked about but hasn't made.
If it were me, I'd like gift cards for filament, maybe some kind of storage or drying containers for filament if he doesn't have any, maybe some upgrades for his Endor 3 that he doesn't have like a BL Touch, silent board, upgraded hot end, better build plate, etc. Maybe a subscription or gift card for a service like The Spaghetti Detective (now obico) or to someplace if he buys STLs or other services. These are just off the top of my head.