In an effort to make small form factor PCs even smaller, HDPLEX has created an internal power supply for them. Added benefit: it's fanless and supports up to 80W. This is designed to replace the power bricks that are apparently common for most builds, meaning that you have one less thing to hide behind something else.
The unit takes up 121.5mm x 30mm x 40mm, which works out to 4.8”, 1.2”, and 1.6” for people who like measurement systems without simple decimal shift conversions. This is on par with some external power bricks that I've seen for the NUCs, although those are 65W (the same as Intel's official brick) while this one is 80W. I'm not sure what that extra 15W will get you though, unless you jump into the Thin-ITX form factor, which is also supported.