For the majority of us, pasta water is useless and is meant to be discarded after you have boiled your pasta.
However, you can re-use that water for many purposes around your house as it contains a lot of starch. To stray a little bit away from the story, we have a dog at home and once we cook pasta or spaghetti, we give the dog that water and she absolutely loves it - finishes it in a matter of seconds. But besides feeding it to the dog (You may wanna check with your vet first as it may react differently with your dog) here are other was you can re-use your pasta/spaghetti water:
1. To water the garden and flowers.
Apparently, pasta water helps the flowers and plants grow due its high mineral content. So, if you have a small kitchen garden or some flowers outside your house, instead of discarding your water, feed your small kitchen garden with that starch.
2. Soaking beans.
You know how you soak beans overnight so that you cook them the next day? If you do make pasta, use that pasta water to soak the beans. It will help soften them up and make them ready for cooking the next day.
3. Make a soup.
Kinda like how you eat the noodles with their soup, you could use that water to make a soup, instead of using normal water. Not only will the pasta water add flavor to the soup but it will also contain good starch.
4. Clean dirty dishes.
Yup, soak your dirty dishes in the pasta water. Once the starch dissolves, it acts as a cleaning agent and will help make cleaning your greasy dirty dishes easier. Of course, you will need to wash your dishes the normal way the water is just to make the process easier.
5. To make your hair shinier.
Just like rice water is used on the hair by some Asian women, apparently, pasta water can also be used on the hair for shinier results. While I'm not sure if this works for all hair types, it doesn't hurt to try at your own risk. Simply rinse your hair with pasta water and leave it on for a few minutes then go ahead and wash your hair with shampoo and rinse.
(H/T: Boredom Therapy)