Today I was down to the last little bit in my shampoo bottle, but I knew that there was a good bit left, but probably not enough for a shampoo. It's hard to glean that little bit of shampoo that's left because of the narrow mouth at the top, so usually I just toss it. However, I'm a frugal girl and hate to not use everything! I wondered how to put that little bit in there to use. Then the light bulb went off!
I use a foam soap dispenser (I get the cheap antibacterial hand soap, pour about half a tablespoon full in there, add water till the dispenser is about 2/3 full, then shake. My dispenser had only about a third left in it, and so I added some water inside the shampoo bottle, gave it a good shake, then opened my foaming soap dispenser and added it to it. Simple as that! I wish I had thought of it sooner!