Fun stuff!
When I was working Honeywell made room thermostats that contained a small amount of Mercury to make an electrical connection. A lot of them still in use today.
When I was a kid we used to do all kinds of stuff with mercury. It was just in a jar in the chemistry lab. You could tip some out on the bench and play with it. Maybe it has wrecked my brain, but actually I think it's fairly safe at room temperature if you don't ingest any.