If you have a LOT of timers...
then this is a pretty awesome and cost effective little tool. The company selling it is too goofy for words, with all their obnoxious advertising. But if you can get beyond that, you lay down $50 for a some PC software that lets you set up as many, wickedly sophisticated, timers that you want. You then download the timers into a little module through your PC's USB port. You plug that into the wall and it executes all the multiple timers you've set up. But the catch is that you have to have purchased an X10 lamp or appliance module for each thing you are controlling. The little x10 modules cost from $5 (Internet sales) to $14 (radio shack), depending on where you get them.
But it works great. I've got timers on my CO2, UV, 4 different banks of lights, an air pump, a valve that drains my tank, and a pump that fills it, and lots more.
It's worth a look if you've got lots of timers IMO.