@NiMa: Well, it's basically just that, a run action on the loop0 device in an udev rule. Check my answer to @fulldecent's #25 on GH

. (Or, basically anything that uses it, e.g., most of @frostchutz's stuff or how KoboStuff launches its services).
@trksh22: Well, you just linked to it in your quote. Read that, and the links therein (and the links therein again ;p).
Remember that it will cause Nickel to *delete* said stuff, so, if it's actual user content, back it up, and as far as KOReader/Plato are concerned, you'll have to reinstall them.