Why do you find social media useful as an academic?

I asked this question on Twitter earlier today. Here are some of the answers I got:

https://twitter.com/catherinecronin/status/719576281067732992

https://twitter.com/FrankPasquale/status/719506184034758657

https://twitter.com/slewth/status/719515505506258945

https://twitter.com/Work_Biscuit/status/719515165176238080

https://twitter.com/raphahead/status/719524427730415616

https://twitter.com/HelenBarcham/status/719522477248876544

https://twitter.com/newbiephd/status/719542148983603201