I got a $12 (maybe $15 I forget) digi timer from Home Depot. I can find the brand if your interested. It was a 3 prong connector (most of the cheaper timers have no ground) and it has a whole host of options on it, but I only use a standard lighting schedule:
-turns light on at 6:30am
-turns light off at 10:30am
-turns light on at 1:30pm
-turns light off at 9:30pm
I have it run like this 7 days a week, but am thinking of switching it to turn on later on saturday and sunday since I normally try to sleep in and I want to keep the fish on a routinue (normally they are fed in the morning 5-10minutes after the lights first go on).
Well worth the money, and the break during the mid-morning when I'm at work seems to have helped control some slight algae issues (too many variables to say exactly why).