On Sun, 12 May 2013 21:42:24 +0000, John Weiss wrote:

Try Goo Gone or Goof Off or similar product made especially
for dissolving gummy things.

We looked up the main ingredient in the Goo dissolvers; they
appear to be 95% petroleum distillates.

We tested a few petroleum distillates, such as carb cleaner,
MAF cleaner, paint thinner, engine degreaser, etc., but what
worked fastest and easiest was plain old California gasoline.

In fact, I tried a new technique today, which was to put the
plastic jars inside a mixed-nuts container from Costco, and
shook it for about 10 seconds; then washed it off.
http://www3.picturepush.com/photo/a/...g/12918691.jpg

Worked like a charm!