Well, freezing cels has never seemed to hurt them 
before. It seemed to do nothing to the ones I 
tried it with, although I can't imagine it would 
be good for them if done repeatedly, and I KNOW I 
need to be fabulously careful to not bend them 
while they're cold. . .

What would your friend recommend for unsticking a 
sketch? (Knowing that I'll allow for some damage 
or potential damage to the sketch, but not the 
cel.)  I mean, if nothing else, it *will* be 
removed in the end - even if it means the demise 
of the sketch - simply because I *hate* seeing a 
sketch behind the cel like that. But I'd rather 
try to remove it in a way that chances saving it 
in as undamaged a form as possible.

Many Sharp Smiles,
--Drac