I have just recently started designing very basic models to print on a free program called TinkerCad. The very first thing I designed was a block that screwed into a light-switch panel. On the block was a loop in which a sting would go through. The string was mounted at the top of the panel and ran through the loop over the light switch button. The string was then routed through my room to my bed, where I could pull on a handle I designed to turn off my lights whilst in bed.
The downloads for my designs can be found here.