"Great lakes gelatin" has a couple different kinds. I know they have atleast 2, 1 which you have to add to hot water and then chill "like jello". The other kind you can add to cold liquids, which becomes very convenient.
Yeah i mix the cold soluble "great lakes gelatin" in my orange juice, stir thoroughly, and drink like normal orange juice.
Here is a link to the cold soluble gelatin at the bottom for a reference (i didn't price check, so this link might not be the best deal).
http://www.iherb.com/Great-Lakes-Gel...w&gclsrc=aw.ds