[Solinoid]

This. Not sure why 'Send in x min/hours/point_in_future' isn't a more common feature of communication software.

[pyre]

Using the Unix philosophy, you're supposed to use `mail` and `at`. ;-)

[freelancezombie]

I use boomerang in gmail specifically for this.

[Solinoid]

I'm aware of it, and I can't believe such a simple service is a paid add on.