You still don't know, do you? That's ok. They aren't exactly common household items. My friends, you are looking at a pile of carpet samples. That's right, carpet samples. Thus the whole art you can vacuum thing.
I got these 5 years ago when I interned with an interior architecture studio. You see, to advertise their product most carpet companies distribute little squares of actual carpeting, like this:
image from Berber
But there was one particular carpet-sample kit that contained hundreds of little tubes of bundled carpet fibers. I thought that was just too unique to pass up. Luckily for me, the studio was thinning out its material library and more than happy - albeit a little confused - when I offered to take it off their hands. I had no idea what I would do with them, but they came home with me all the same.
After I had my boards all set up (a 5 x 5 grid, if you remember) I got to the task of sorting through A LOT of cylinders to create my patterns. I decided I wanted to make 3 color gradients, and with so many similar carpet shades to choose from I knew it would be easy. Naturally I chose to do gradients for blue, gray and yellow to match the color scheme of my living room.
After I had my pattern set I used small adhesive labels to number each cylinder in case something (most likely one of the cats) messed them up before I could install them in my boards.