I have one latex lined box pouch that folds and snaps closed. I don't use it much for a few reasons.
I'm normally not out where I can enjoy a bowl or three enough to keep extra tobacco with me. I also normally carry my 6 pipe leather bag that also holds a tin of tobacco. The last thing, is that while this is good for a temporary travel, it does tend to suck up the moisture real fast and gets gunked up from aromatics fast. I hate wasting tobacco and I tend to fill it up a little too much if I do use it.
However, I can see it being something of a great thing for if I chose to just take it and pocket my pipe and tools...Just as long as I remember to smoke the baccy that day, or put the leftovers back into the jar when I get home.