Is a movie prop the ultimate laptop bag?

A while back I attended a Cloudflare board meeting and carried my laptop in a brown paper bag from a grocery store. This elicited a few comments about needing a real bag. But I've often carried my laptop in inconspicuous bags. For me, the ultimate laptop bag is one that looks nothing like a laptop bag; it should look like nothing special at all. Unhappily, grocery bags are not very strong, but…