I don't feel I should pay for such a thing.

then don't I made one and the free tier is generous enough that most people just stick to the free (much to my despair) ^.^

See also http://focusmate.com, http://focus101.com, http://caveday.com, and many more!

focus101 is totally the best one and I'm not saying that because I built it :D

Tried most of them! Caveday is just too many people in a room and the rest are really awkward just one-on-one. Flow club hits the midpoint, with 4-8 people in there, everyone has stated goals and it's obvious when someone is missing their goals.

It can still be a liiitle hit or miss depending on the club host. But a good host on a pomodoro session with actual verbal check-ins is 100x better than coffee.

Focusmate discussed on HN before, eg.

https://news.ycombinator.com/item?id=21352305

Focusmate – Virtual Coworking Helps You Get Things Done, 64 comments