Fresh stains are the easiest to treat, of course, but even the older more established spots can sometimes be removed.

Laundry stains on washable fabric: Combine equal parts of water, liquid dishwashing detergent and ammonia in a small bowl.  Start with small proportions as it does not keep for longer than a day or so.  Use an old toothbrush to rub the solution onto the stain, and launder as usual.

Loose dyes in the wash?: There are new disposable sheets called "Color Catchers" by Shout that you simply put in your washer and launder with clothes as usual to keep your clothes looking crisp and free from those pinkish edges.  Works for all colors.  Find this at Wal-Mart.

Hot water: great for Kool-Aid and Jello type stains.  Rinse and soak as needed.

Goop: apply liberally then let sit.  Put it in your regular wash.   This is an inexpensive product to try on fabrics that have been washed with crayon.

Biz: Great for soaking all kinds of stains loose.  Just soak in the sink then wash as directed in the washer.

Mother’s Miracle: Great for removing spit-up, urine, blood, etc.  What new mom or grandmother can do without this?  This product has been found at Baby Superstore.

Tilex: Did you know that you could try this product normally found in the bathroom on white clothes with mildew stains?  It is a bleaching product, so beware and use carefully.  On white clothes, just spray on the stain and let sit, simply rinsing if you see blue spots appear.  Using Tilex on colored clothes should really be a last resort as bleach spots are easy to cause.

Oops is a latex paint remover that has worked well to remove stains, marks and stickers from of plastic toys.  Test the toy if the plastic is thin, but most thicker plastic toys such as Little Tikes will do well.  This will also take crayon off of chalkboards without damaging the finish! Remember to wear rubber gloves! Find this product at Wal-Mart and most hardware stores.

Shoes and laces: You can make your shoes look better by using a spray solution on scuffmarks. Find this solution at shoe stores.   
Soak your white laces in Biz and your shoes will look 80% better!