Every year, when we put up Christmas lights, we struggle to find a good way to attach them to bricks. Usually we use tac - sticky blobs of goop designed for temporary attachments - and every year they fall down. Tape doesn't stick long enough either. What I'd like to be able to do is 3D-print some custom brackets that snap onto my brickwork somehow and allow me to thread the light cables through. That way they should stay put, the lights work properly, there's no gunk on my bricks afterwards and I can reuse them next year. If I had the modelling software, I could probably order them straight from Shapeways or something.
Mokalus of Borg
PS - But then again, for the sake of easy attachment, it might be too expensive.
PPS - I haven't really looked into it.