[Snowman]

As far as creating your own magic concoction, you could just start experimenting with various solvents and see how the cards hold up. And yes, water is a solvent. In fact, it's referred to as the "universal solvent" because it dissolves more substances than any other liquid. Other solvents that I've read about people using are vinegar, isopropyl alcohol, Bestine, lighter fluid, bleach, hexane, heptane, naphtha, H2O2, ethanol, toluene, and even gasoline. Some people also use various soaps and degreasers on cards. But many of these options are detectable and can leave a residue on cards, if not completely destroy them.

My advice: don't use bleach! You'll ruin the color and make the card brittle. Don't use lighter fluid either. You'll end up with an oily residue on the surface. Don't use something like gasoline or Bestine either. Pretty much anything you can buy like that which has solvents in them and other additives are a recipe for disaster. Don't soak a card in pure isopropyl alcohol either. It will cause the inks to bleed.

Spend some time researching paper conservation. There are all sorts of excellent resources out there. Museum conservators know how to safely clean valuable historic documents without damaging them in any way. From the US Constitution to ancient scriptures to Shakespeare's original writings, they work on it all. Documents that are far more precious than sports cards.

If you find a solvent you want to test out, try pouring a small amount of it into a glass container first and let it dissolve. Then check to see if it left a residue or if it dissolved cleanly. Some solvents won't leave any residue behind at all. Others will.

Other good resources are general cleaning blogs and forums. Also woodworking forums. Most woodworkers have experience with a wide assortment of solvents. There are all sorts of excellent resources out there that are made by people who are passionate about cleaning anything and everything. That's how I discovered that vinegar removes gum stains, by researching how to remove gum from my daughter's hair.

Every stain is different. There is no one way to clean all cards. Some stains are caused by water, others by soda, coffee, sugary substances, red wine, acidic paper stock, tape stains, gum, wax, glues, etc. And all require different techniques. Some can be removed, others cannot. You just need to test out various ways to clean different types of cards. What works on one card might ruin another. As an example, even just water will cause the reds on 1954 Topps cards to fade. Vinegar will cause the yellow on the backs of 1961 Topps to bleed. And hot water will cause the blue/green on the backs of 1961 Fleer basketball to bleed. Temperatures matter as well. Adding energy to water is often a better solution than adding something like a soap or isopropyl alcohol. High-frequency sound waves like those produced by an ultrasonic cleaner also work great sometimes. And despite what all the purists will have you believe, sound waves don't actually damage a card! I know, shocking!

I've studied this topic in great depth and have cleaned thousands of cards. It's fun to me. I enjoy the scientific process. What I've learned is that the vast majority of what you read on baseball card forums is misinformation. If you want to learn how to clean sports cards, then your best resource is to learn how to safely clean something else first, then see if those techniques work on cards as well. The best thing to do is just read, read, read, and then read some more. Then test out various techniques on commons from the sets you're interested in working with.