What do you get when you mix one part glue, one part liquid starch a little bit of food coloring? You get 100% fun with GAK.
If you have kids this is a great way to introduce them to science and have something fun to play with afterwards.
When my son was younger he made something similar at our local Science museum except it was called OOBLECK in honor of Dr. Suess's birthday. Not only did my son have playing with the finished goo, he learned a little bit about science and mixing chemicals make a different substance that has the properties of both but not exactly like either of them to create a new substance.
Oobleck is from the Dr. Suess book "Bartholomew and the Oobleck" which has the moral of being careful of what you wish for. King Derwin, who is bored with ordinary rain and fog and wished for something different and gets his wish when the sky starts raining Oobleck, a sticky green substance. King Derwin is first thrilled with this as it is different, but his delight turns to horror it continues to come down it gums up everything in the kingdom. The book goes on, in rhyme in increasing pace as the Obleck continues to invade the kingdom and the kingdom's efforts to try to solve it. The day is saved in the end by King Derwin's page, Bartholomew.
For instructions on how to make your own, visit Make It and Love It where Ashley had created step-by-step pictured tutorial. http://www.makeit-loveit.com/2010/05/making-gak.html