The Lightbulb Computer is a speculative device combining a projector and computer vision in a lightbulb form factor that mounts in standard sockets or portable lamps. It projects information and augmented reality overlays onto surfaces in everyday spaces, responding to voice commands and gestures to enable hands-free interaction for cooking, studying, trip planning, smart home control, and ambient displays. The design offers an alternative to smart glasses by keeping computation ambient and spatial rather than confined to phones or facial devices.