I've been trying to think of ways to encase the cord into something that I like to hold, feels good in your hands.
I've pondered this myself, I came up with two possible solutions, both involve paracord. The first which would be the easiest would be to look up "paracord cord protectors" on like youtube, there is a few videos where they show you how to braid a paracord around your cord (first you remove the stuff in the center to make it more pliable. This would take time, but you could pretty much make something look pretty slick but it may take some time, basically looks like those paracord bracelets, only would be the length of the cord. The second option and this is where i'm implementing some of my southern engineering, so will take a few tools and basic technical know how. Find a length of paracord with a color scheme you love. Remove all the white filler cord in the center of the cord. (The following instructions may void your power adapter warranty so proceed at your own caution). Remove the two screws on the back of the power adjuster in the center of the cord. There are four solder points you are interested in, the cord coming in from the wall and cord going out to the Nano (since it's closest to the Nano you may only want to do that side). Taking a soldering iron unsolder the cord you will be working with, make a note of how you removed the cord (there is a smooth side and a side with ridges on the cord). Cut the length of paracord you need, a little longer is better you can always trim some off at the last step. Take out the center stuff, if its a little hard scrunch the paracord (think of chinese handcuffs) Take two 1-2 inch piece of heat shrink tube, this can be found in most warehouse stores, electrical supply, radio shack, amazon etc. it comes in different sizes and colors, any color is fine, but you want a diameter big enough to slide over the paracord and slip over the cord. slide the two heat shrink pieces to about the center of your cut paracord. The next step may be easier if you wrap the two wires you just un-soldered with some electrical tape. Next slip the paracord (with the heat shrink tubes on it) over the cord, till it's covering the cord end to end. Take one of the pieces of cut heat shrink and slide it to the end, don't slide it off the paracord, what you are going for is the heat shrink is covering about half paracord and half cord at the very end, then use a lighter to shrink the tube down it should stick real good to the cord and the paracord making a nice looking/sturdy transition. Now trim the end by the bare wires till you have a length that will just be coming into the control box, slide your other heat shrink piece down and seal that end the same as the other. Then re-solder your wires back to the board. If you are doing the other end repeat steps, re-solder and reattach the back of your heat controller, the case should hide and hold the shrink tube well. I haven't done these steps, again this is just mind engineering of what I would do if I did this.