I run a Mastodon instance at bbq.snoot.com for film/tv folk.
We are currently accepting open signups, although this might change in the future. This could be a great Mastodon server for you if you work in film/tv or if you just love talking about movies and TV shows.
Click here to join the bbq.snoot.com Mastodon instance.
If you don't think of yourself as film/tv folk, and you still want to join Mastodon, you can find a wide list of potential servers at the Join Mastodon website.