The Lix has recently come out and essentially supplanted 3Doodler as the darling of the 3D printing pen market, a position which belonged to the latter by virtue of being the only one of its kind up to that point.
Now, a third 3D printing pen has appeared, the so-called Cloudio2go, which is similar, in girth, to the 3Doodler, but is a bit more colorful and not quite as large or hard to hold.
It has an adjustable spinning speed, a plastic shell and the ability to use ABS or PLA mixed color filament strips.
In fact, if you drop by the Indiegogo crowd-funding campaign for the Cloudio2go 3D printing pen, you'll be able to get the pen and thirty twelve-inch filament strips for a pledge of $89 / €89.
In case you don't know how a 3D printing pen works, it basically lets you draw things in 3 dimensions. You can start with, let's say, a square on a piece of paper, and work your way up, or you can just start to grow support beams in anticipation of building a house or something.
Your imagination is literally the limit here. Well, that and your supply of filament at any rate.