Carrying Case:
VP1 - I found a pocket knife case from Victorianox (Swiss Army knife). It fits the VP1 batt and the atty/cart perfectly. It protects it while in your pocket, on your belt, or hanging around your neck (I attached a cord).
510 - I just use the 510 carry case, holds 2 batts, atty, extra cart and adapter. Mainly just put in a shirt pocket.
VP2 - Since I just got it today, I'm looking for a case. A multi-tool case might do the trick.
Vaping Bag:
I use a small bag with lots of little pockets that fit attys, juice, batts, chargers and everything. It's the boarding bag from Victorianox.