CasparCG at BBC Scotland
youtube.com
youtube.com
It's open source, and getting widely adopted. It's very niche, but with a big impact - millions of people see graphics rendered by it every day, but only a few dozen use it.
I've used it in my student days at the student TV station - no budget means free is pretty much the only option, and I thought it was incredible that it's just rendering any HTML to make it look so professional - here my own football client from a couple of years ago [1]. And now the BBC does that same.