Weed Killer Recommendations

I am looking for something that will the weeds but not the grass. Any ideas retail or homemade are welcome.

Thanks.

Any weed n feed will do it. Mix per instructions then add 1/2 cup laundry detergent per 2 gallons of mix. The purpose of the laundry detergent is to prevent the substance from beading and rolling off the leaves of the weeds. If the poison makes it to the roots it will actually feed the weed. When you spray, lightly mist the leafy part of the weed. Do not over do it or you will actually be watering the weed.
Repeat this process every 2 days until the weeds are gone.

These instructions were given to me by a crusty old guy in the garden section of home depot. It has worked like a charm every time I have used it. The only thing it has not worked on is nutgrass which requires a very specific agent to kill.