Things we built because we needed them ourselves. They are free, they need no account, and they work on any file, not only the ones you bought here.
Drop in any STL and find out whether your machine can make it: size against your work area, carved depth, the board thickness you need, how much detail each bit would smooth away, and roughly how long it will take.
Runs in your browser. Your file is never uploaded.
Design a one-piece printable lampshade in the browser, change the profile and the weave live, and download the STL. There is a free demo and a standalone Windows desktop version.
Prints in vase mode with no seam.
Something you keep doing by hand that a tool could do for you? Tell us and it might end up on this page.