There are so many shapes, colors and styles that I couldn't possibly show them all, but here are a few of my favorites in my own collection:
This time I went with classic round Enamel Dots since they look the most like gumballs! To make the machine, I printed out a piece of copyright-free clip art and used it to paper-piece the machine from cardstock and patterned paper. I filled my machine with all different sizes of gumballs, since that makes a design more dynamic. Plus, it filled the space better! ;) For the gumballs at the very bottom of the machine, I used my stout craft scissors to snip one edge flat, so that it would look more realistic.
For the background I made my own patterned paper by filling a 4x6" panel of white cardstock with neat strips of colorful Dot Washi Tape. I printed an appropriate computer-generated sentiment et voila! Would you care for a gumball?