timered startup

I'm setting up a torrent box to conserve power, but I don't want the torrents running during the day when the internet is actually being used.
To get the computer to shut down at a specified time I'm sure is easy to figure out.
What I'm interested in is having the computer turn on at a set time.
I've already got everything to run automatically from boot, I just would like to have it power on on it's own.

Are there any current products that do this, or instructions on how to easily make one?

What I'm interested in is having the computer turn on at a set time.
Mac

Even an old one. It's in system prefs under "energy saver", then "schedule"