Has anyone ever made an overhead lift?

I'm not talking about an elaborate multi-room system, just a simple 8-10 foot metal bar on the ceiling with a roller and electric hoist that would lift you up and allow you to roll over into your wheelchair. A new system costs upwards of $5000, but the parts can be purchased for about $500. These items were not designed for people, but if they are rated to hold about double your body weight and its installed securely, why not go the DIY way?