I finished making a giant batch of laundry soap the other day and that reminded me of the little bits of bar soap that I've been collecting. Yes, collecting. I can't really call it a "dirty little secret" because it's soap... and therefore not all that dirty when you think about it. The process goes something like this:
The bar of soap in the bath or on the sink is used until it resembles a miniature cuttlebone. We stop using that bar of soap. It sits in the soap dish for a day or two (while we use the soap from the other bathroom location) until either my spouse decides to open a new bar of soap or I open a new bar of soap. The person doing the opening of the new bar is very important. If he opens the bar, he will moisten both the old and new bars and affix the old bar to the new bar by squishing them together. I don't find this to be a very successful method because, for me, the little semi-adhered bar just slides off as soon as I start to use the new soap. He, however, swears by this method of using up the tiny bar and in the interest of peace, I don't fight it. Plus, if I were really that adamantly against the method, I'd have gone ahead and dealt with it myself before he could do his grafting.
Now, if I am the one changing the soap bars, I will use my soap-sock as a receptacle for the tiny bar and quite happily dump the pristine new bar into the empty soap dish.
I cannot take credit for the soap-sock invention. That belongs to my mother... or maybe even her mother... I'm not entirely sure. I know that we did this all the time as I grew up. Whenever a pair of socks developed holes that could not be easily repaired, they went into a "rag-bag" of assorted bits and pieces. Some of these were destined to become soap-socks. To make a soap-sock, simply turn the sock inside out and sew across the toe area to close off any holes, then turn right side out again. Stash the sock in a convenient, but out-of-the-way location in the bathroom and fill it with the bar soap remnants as they become available. When the sock becomes somewhat full, preferably after accepting a soap remnant from the bathtub, sew the opening shut. Then use the soap-sock in place of a bar of soap in the bathtub. The sock acts as a washcloth while holding all the little soap bits together inside. Do make sure to not leave it sitting in a puddle of water, though, or you'll end up with a soggy mess of soap squeezing out of the sock.
While the soap-sock method works, I have recently started using liquid soap - especially beside the kitchen sink where a bar of soap just wouldn't look right. Liquid soap can be expensive, even when you purchase it in large refill jugs. Plus, the empty dispensers and refill jugs become so much more garbage for the landfill. I found a solution! I have discovered that, with a minimum amount of effort, I can turn those collected soap bits into liquid soap to refill my pump containers.
Instead of putting the soap bits into a sock, grate them into a small jar until you have at least 1 cup of shavings. Technically, you could use a pristine bar of soap for this as well, considering bar soap is usually cheaper than liquid soap. (Note: I don't recommend using an intensely moisturizing soap for this method, it doesn't seem to turn out as well as "plain" soap.)
Once you have about a cup of shavings, put them in a saucepan with 2 quarts of water and bring to a simmer. Stir gently until the shavings melt completely. Take off the heat and stir in 2 Tablespoons of glycerine. You can usually find glycerine in the health and beauty section of Wal-Mart, in soap-making sections of craft stores or in pharmacy sections of grocery stores. Now, let it sit until completely cooled. This may take several hours or even overnight. Stir again to check consistency.
If it is too thin, in a measuring cup mix 3 Tablespoons of table salt in 8 oz water and add this mixture 1/4 cup at a time, to the soap mixture - mix each addition thoroughly and give it time to rest between additions - keep adding the salt mixture until the soap reaches the desired consistency. If you get through the entire cup of salt water and the soap still isn't thickening, warm it up and add another half cup of soap shavings, stirring until they melt completely. Let it sit overnight again and it should be thick enough for use.
If it is too thick, stir in some more water, one cup at a time, until it is the right consistency.
Just be careful not to mix several different strongly scented soaps in the same batch. Adding Ivory to Irish Spring is fine, but mixing Irish Spring with scraps of Lavender/Vanilla ends up smelling icky. (It does still work, though!)
Once your batch of liquid soap has cooled completely, you can use it to refill your dispensers. Store any leftovers in a clean, capped jug and shake before using.