Always, I was out last night. Technically, you cannot cross onto a property during dark hours, otherwise it is a charge, but the streets are fair game, and the weather is so great there are a few people wandering.
I enjoy the UV light, but I enjoy the fresh night air and peace even more. Alot of hustle bustle during the day. All those Romans doing Roman stuff.
A little sad seeing the night crawlers shit faced and too broke to take a cab though.