Not for sale, but a cool DIY idea, especially for a kitchen, is the in-store design in New York's Anthropologie store, found by Apartment Therapy (I love those guys!).

A round cord with a basic plastic fitting mounts through the cap to a refrigerator light (the long, tube kind). Just screw the clean, empty milk jug back on, hang as a pendant, and you're done.

I wonder if there's a CFL bulb that would fit the bill?

Link