the sixth studio album by British progressive rock band Porcupine Tree, first released in May 2000, and later reissued in 2008 on CD, DVD-A surround sound, and vinyl.

A lightbulb joke is a joke cycle that asks how many people of a certain group are needed to change, replace, or screw in a light bulb.

A lightbulb socket, lightbulb holder, light socket, lamp socket or lamp holder is a device which mechanically supports and provides electrical connections for a compatible electric lamp base.

A nuclear lightbulb is a hypothetical type of spacecraft engine using a gaseous fission reactor to achieve nuclear propulsion.