...actually I think someone called it laundry mousse. I think that sounds more fun.
I stumbled upon this post last week about it. I've been using the dry homemade laundry detergent, made from 1 bar grated soap ( I use Ivory but there's also Fels-Naptha and Zote), 1 cup washing soda (not baking soda) and 1 cup Borax, for over half a year now. It works like a charm and is the best money saver. I almost feel guilty making it. The biggest problem I have with it is that you have to use a dust mask, which I keep forgetting to buy, to mix and use it because the dust isn't good for you. There's also a liquid detergent made from the same ingredients but it literally makes a 5 gallon bucket! That's too big for me to store, especially since it lasts forever.
So I followed the trail of links back to the source at the White Silk Purse blog. I like to know where things originate from online if I can find it. This recipe makes a bit over 1 gallon that you store in quart canning jars and has no dust. It's exactly what I want so I made a half batch this weekend. I used a whisk to stir it up, followed a commenter's advice on how to add the powders and it came out nice and foamy so I didn't need to blend it. I didn't even wait for it to sit the 8 hours it recommends and used it right away since I was running out of powder. It looks like it worked as good as it always does. I use 2 tbsp in a large load, I don't have an HE washer, so I should get over 60 loads from what I made. I can't recommend this enough. It's the best and cheapest laundry soap ever.
If you want pictures, check out the links. I couldn't do as good of a job as they did so I didn't take any.