I usually do the Scott's program. This year I'm trying the lawn tonic route. You make it yourself with beer, soda, ammonia, dish soap, and mouthwash. I got the recipe from some old news report. I bought all of the ingredients today and plan to start next week after I mow. If it actually works, I'll let you know.
Here is a link:
http://water.ksl.com/index.php?nid=3&sid=92192