here are some links to things that i find useful/cool.
makercase; quick and dirty box generator. good for laser cutting.
protolabs injection molding guide; super clear, actually useful when you’re trying to make something real. also they give you a free cube.
thingiverse; still a go-to for quick inspiration or parts you don’t feel like modeling from scratch.
jlcpcb’s cnc service; surprisingly cheap, decent quality. good for fast protos.
tinkercad; sounds silly but honestly amazing for explaining ideas or doing fast rough CAD without getting stuck in a real program.
convert3d.org; lifesaver when you’re stuck with a cursed file format.
phosphor icons; clean, flexible icon set. i use these everywhere.
hugging face; a lot of AI noise out there, but this is where the actually useful stuff lives.