As CRTs find themselves ever more relegated to the dustbin of history, they grow in appeal for tinkerers and artists who enjoy their analog vibe. For most of us, it's not practical to keep bulky old TVs lying around, cool as they may be. Fortunately, the popularity of camcorders in the 1980s and '90s means there are plenty of tiny CRTs available in the form of viewfinders.
Being somewhat older technology, they tend to accept composite video signals, which makes them easy to work with. Since they were designed as an add-on for portable, battery-powered devices, they have relatively low power requirements.
I've recently picked up a couple of these viewfinders, and I'm going to use them for electronic art projects.