On the U.K. market is a product called "Everflex Silicone Eater,"
that comes in a half-length cartridge to fit standard sealant gun.
See http://www.everbuild.co.uk/silicone-eater 

It claims to "Remove all types of silicone sealant from Baths,
Kitchens, Worktops, Basins, Showers, Door and Window Frames,"
and to be "Harmless to most surrounding Surfaces."

It requires bulk of silicone to be cut away with sharp knife and then
two to four hours to dissolve the residue, which is water-washable.

I haven't tried it on anything.

Barrie Land

 [ This article of 1983, "Removal Of Silicone Adhesives," describes
 [ a compound similar to the formula of "Everflex Silicone Eater:
 [ http://cool.conservation-us.org/coolaic/jaic/articles/jaic22-02-007.html 
 [
 [ A patent on a dissolving agent for cured silicone rubber,
 [ entitled "Thickened silicone dissolving agent," is
 [ described at https://www.google.com/patents/US6793741 
 [
 [ Search at Google for "cured silicone solvent".  -- Robbie