This is an idea for a more compact, compact flourescent light. It comes in three parts: the ballast, and the adapter, and the lamp.
The ballast would plug into the wall, and have a recess in it, into which the lamp's original plug would be inserted. The lamp's original plug would be held in place
semi-permanently, by a screwed down cover.
The adapter would then go into the light bulb socket (either using an edison base screw, or a bayonet base, or whatever's appropriate for the original lamp). This adapter would be designed to be easy to put in, but difficult or impossible to remove. This adapter would be designed to fit wholly inside the regular lamp socket, so as to take up a minimal amount of room.
Into the adapter, one would then put a flourescent lamp (either u-shaped or spiral), probably with a two pin base.
The adapter of course would be designed to only work with flourescent lamps approriate for the ballast.
The flourescent lamps would *not* be specialty lamps, but ones already available, and thus readily purchased, in hardware stores in the country/region where the device is marketed.
Although the adapter wouldn't be removable from the light fixture, the flourescent lamps would be easy to change, and, with the aid of a screwdriver, it would be possible to replace the ballast, too.