Back in the 60s, Mattel had a toy called the Thing-Maker. You poured the Plastigoop into molds, put the molds in a special oven and out popped your own wiggly creepy crawlers, mini-dragons, toy soldiers, or for the girls: flowers.
Mattel has recently resurrected ThingMaker but as a 3-D printer. With their new version, there are a lot more colors and they have sought to make 3-D printing easier to do. There is an app already available so you can see the items that are ready to be made. You can change out the parts you can choose from to customize your item. You can choose colors, textures, backgrounds, and take a photo to keep. From the app, you can send the items to the printer. It will tell you how long it will take to print and how much the item will weigh when done.