I found a nice professional-looking (or at least tech-looking) container to hold my vaping equipment. It doesn't need to be modified to be useful, but some minor mods could improve it's usefulness (see below). It's a USB drive container by Case Logic. I found it at Staples, I guess most office supply stores and some computer stores would have it. The model is JDS6 Black.
I include pictures of it closed, and open full of vaping stuff; you can see it has mesh slots with room for several batteries, attys, and cartridges; There is even room in the slots to slide in a 10 ml bottle of eLiquid. I am still looking for something smaller, but this case is not oversized, about 5.25" x 3.75" x 1" when closed (13 cm x 9.5 cm x 2.5 cm), easy to slip into a jacket pocket for example.
Possible modifications include elastic bands across the inner binding to hold a whole eCig (it's 120 mm high inside, large enough to accommodate many models including the 901 and 510), and a padded section to separate and protect facing items from scraping one another if the case is compressed.
The case is heavy duty nylon construction with a stiffened binding and sides (plastic or cardboard I assume), and it zips open and closed easily with a big fabric zipper pull. It is slightly padded on the front side.
