Just want to add a quick note to this thread regarding Dura-Lar Wet Media film. I was at the art supply store the other day, and they had a pack with a dinged-up corner that was significantly discounted. I have no use for it, really, but I grabbed it thinking of this thread. If anybody wants to try it (US only, probably, otherwise postage gets too high), I'd be glad to send out a few 11x14 sheets rolled in a tube, or cut down to 7x11 for mailing flat. I'd ask that you reimburse me for postage and shipping materials. If anybody's interested, let me know via PM.
I took a little corner of it and ran it under water. There is definitely a clear coating that got a bit slippery for a second before it rinsed off. Have no idea what it was. The highlighter markers that I had laying around (which I thought were water-based) didn't behave any differently between the wet media film and regular dura-lar, so maybe they weren't water based, or...
Anyway, just wanted to mention this. If it works, it might be a good option for those who wish to avoid the larger purchases required for the 3M film if you're making sheets.