Here is an interesting site with many people writing in their ideas on how they did their preps.
ibdcrohns.about.com/u/ua/colonoscopy/colonoscopypreptips.01.htm (Oh no, I can't get the link to work!!)
I read through a few pages and didn't see anyone try to make jello out of the prep, BUT, a couple of people did put the powder type of prep into gel caps instead of mixing it with water. Hmmm...! Here is one post describing this method:
"After 11 Colonoscopies...
...this will be my 12th as I have severe Crohn's disease. What's my secret? GEL CAPS. Every time I have a bowel prep I buy quick-dissolve empty gelatin capsules (you can find them at vitamin stores) and fill them with the Miralax powder, as it makes me gag and vomit no matter HOW slow I drink. It may take a couple hours to fill the caps but then I can take them on prep day, no bad taste! And they don't appear on the scope at ALL as they are clear gelatin.
—Guest Kate"