Alright, this is scary business, but I went and did 
it.  I had my two lone tenchi cels professionally 
framed at a local frame shop.  Bear in mind, I 
called around and asked if the framers had any 
experience with cels.  About 100% of the responses 
were "Huh?"  Yeah, my heart sank when I heard that, 
but I still wanted them framed.  So I went with a 
place that had never framed a cel before and let me 
say they did a fantastic job.  They used the 
preservation method (I know it was called something 
similar to that) were I had them use all the acid-
free stuff and special glass.  My only concern is 
that the cel really isn't raised off the 
background.  (Background being a matte.)  Also, I 
see no way in heck to open the frame and let the 
cel breathe.  It's a bummer I tell ya.  But I've 
only had them framed for under a month.  I'm hoping 
nothing will happen to them because the framing 
cost more than the cel!  Heheheh, prolly silly of 
me to do that, but oh well.  :)

I took pictures of the cels, but film hasn't been 
devolped yet.  I need a digital camera.  Anyways, 
I'd go and have them framed.  Maybe start out with 
your least favorite cel and see how it goes. :)