For Android there is TimeLimit.io which is open spurce and in the F-Droid store.

Using this with Steam to prevent games from updating.

What is with the young man who had to defend the motherland in the great patriotic war?

For Gnome there is GSconnect available.

Is coreboot doing something like this?

Please make sure it doesn’t contain any bugs which can be exploited.

If possible I get the Git repo from the F-Droid entry for this app. And I usually look at the activities and commits. I hope that helps.

Die someone already mention the Apollo 14 computer hack .