This is going to blow your mind. There is a kickstarter fund going on right now for a 3D printing pen. It was hard for me to imagine how that actually worked until I watched the video. It is pretty cool! You insert plastic filaments and it heats up and works somewhat like a hot glue gun, but dries quickly. Surprisingly, this pen is pretty affordable! I’m not sure what the final sell price will be but on kickstarter, you could purchase the first version of the pen for $70 and the refills will be around $10 for 10 inserts. For more info check out their website.