Very effective non-toxic etch-resist remover...

[KORGULL]

Concentrated citrus oil*.
I've been using "Orange-Mate" brand non-aerosol spray air freshener to clean sticker/tape glue off of my knife blades and other things for years now. A tiny spritz of the stuff is all you need to effortlessly wipe away stubborn gunk.
Since I started making PCBs recently I tried using it to clean my boards after etching (used photo paper and paint pen for resist) - it works great! It makes it almost as easy as wiping off dust - not much elbow grease required. It also smells great and comes in lemon, lime or mixed fruit scents.
You can get it at some health food stores and I've seen a different brand at Wal-Mart, in the automotive department with the other air fresheners. Any kind that is 100% concentrated citrus oil should work. Avoid any that are dilluted with water.

*It can deform some plastics, so test any materials you are not sure of. I know from experience that it can damage CD cases if you try to remove the sticker glue with it.  :oops:

[MartyB]

Cool Korgull!  Was this with the toner transfer etch resist?

[KORGULL]

Was this with the toner transfer etch resist?

Yes.
I meant to say that but drew a blank on the word toner and said photo paper instead.
I used the copying machines @ Kinko's - the glossy paper they sell there works great by the way...peels right off after ironing. It's pretty heavy weight stock, so it takes a little extra pressure on the iron to transfer cleanly though.