Insecurity Lights

Many homes have Security Lights which switch themselves on automatically if they detect heat, or sometimes movement, within a particular range, after dark. These are intended to scare off intruders and provide a welcome light source to returning homeowners. In practice however, they tend to be oversensitive and mostly scare off cats and other small nocturnal animals, or overreach their range onto public property.

You'll probably be aware of this from walking home in the dark, only to have your weary features thrown into sharp relief, your night vision destroyed, and your heartrate trebled, as a botched DIY project on a nearby house decides you're too suspicious and must have blinding light cast upon you like a prison escapee in a movie.

There's nothing quite like that moment when you're caught in its glare, like a rabbit in headlights, to make you feel paranoid and insecure. It's watching you. Everyone can see you. You can't see them. All those people standing safely in the dark. They have their eye on you. _They know._

Insecurity lights work the other way around. Around dusk they turn on -- fading softly in over the course of a couple of minutes so as not to startle the unfortunate soul walking past at 5:33pm -- but when someone approaches, they turn themselves off, allowing you to carry your darkness with you, and bask in your anonymity.

Ideal for paranoiacs, agoraphobics and others who would rather be curled up in a darkened closet somewhere with a pile of blankets instead of spotlighted for the world to see, they could be fitted to streetlamps as well as private homes, navigation still possible by the dim light spilling over from the neighbouring lamps; some kind of lamp-to-lamp wireless comms, or just ambient light level detection, might be necessary, so that an entire street doesn't get blacked out if several people are walking down it spaced apart. In this situation, the darkness would be spread amongst the lampposts, each dimming slightly.