See this Wall Street Journal article about a really clever idea thought up by the police in Peoria, IL. They've got an old armored Brinks truck outfitted with infrared cameras and labeled "PEORIA POLICE Nuisance Property Surveillance Vehicle."
They park it on the street in front of houses neighbors have complained are being used to sell drugs. Being largely indestructible, it tends to drive drug sellers and drug buyers out of the neighborhood quick.
I like this idea a lot. Suggest it to your police department if these problems exist in your town. The article explains how to outfit the truck for this job. The upside is great and the downside is minimal.
