I have Tom Bihn bags that must be getting close to 10 years old. I have a huge duffel bag, a waist pack, a Brain Bag, a kids cinch-up rucksack, a Café bag (I think large, but who knows), a really slim computer bag, three messenger bags something like the ID but much older (each one larger than the last), a utility tote, the original Buzz, at least four Brain Cells, a Miter, Snake Charmer, both orientations of Freudian Slips, a wallet, checkbook, more than half-a-dozen organizer pouches including some crazy old laptop battery pockets, and the crowning glory: a Super Ego.
As I've upgraded through messenger bags, I pass the previous generation onto my kids or friends. Sold one to a boss once. Gave one along with a Brain Cell as a graduation gift to a neighbor kid with a new laptop (I explained it was used, but they didn't believe me).
As new bags arrive, they come with wonderful paper store-tags that say what they are (and thanks for the cookie, by the way, that came with my new Q-AM strap and horizontal slip); but five years later, I may have no idea what a given bag was called (case in point, which Café bag do I have? no clue). My Super Ego, I'm sure I'll always remember; but what sizes are those other Brain Cells I have lying around the house? For some reason, I recall that the waist pack was called the "Dew Drop" or the like, but I honestly have no idea what the messenger bags were before the Super Ego. All were made before there was an ID.
Some more permanent identification might be helpful when comparing and contrasting. It might let me remember (or rediscover) how old a bag actually is, or what size it is, etc. I guess I could sharpie it onto The Label when it first arrives. Maybe I'm the only one who has this problem, but when you make bags that last forever, they deserve a long memory to match :-) If their name was on the The Label, or other permanent tag, or embroidered unobtrusively, or... well, you get the idea.