I began with
this as my base recipe and ordered large quantities of Maltodextrin and Dextrose online. I found the recipe listed there to be a good start with some changes...
1) A half cup of water was too much. For example, when making a 'double batch', a full cup of water filled approximately 2.5 flasks, not just one. I've taken it back just a hair and keep an extra flask on hand for any overflow.
2) Too much salt. Maybe it was just me, but 1/2 tsp salt made it taste absolutely horrible, and I have a very very high tolerance for 'this tastes like crap but it's good for me so I'm going to suck it up and eat it anyways'. A pinch or two max per serving worked best for me.
3) The juice addition didn't work so well... I found that adding some honey, and maybe subtracting some Dextrose if you really want to watch the calorie content, worked best for flavor.
4) Good news! You don't need to reheat it in the microwave. My solutions remained fluid and tasty straight out of the fridge.
5) Different preparation. My girlfriend works in a professional kitchen, so she does all the 'real' cooking in the house and can take credit for this part...
Drop the Maltodextrin and Dextrose into a small bowl, and then add honey on top if desired. Next, preheat the water in a kettle to a boil and pour it into the bowl slowly while mixing. I found this to be much more effective than the microwave, stir, microwave again, stir method from the original website.
And ta da! You're now your own gel factory and customer!