Haha, I have a "Mad Men" style Samsonite briefcase that my father gave me in the 1970s. Here's a picture of one:
https://www.etsy.com/listing/57044295/samsonite-briefcase-wi...
It works great as a case for my laptop. It's fun being unhip :-)
Edit: I've used modern soft laptop bags, but they tend to develop tears and small holes through which things fall out unnoticed. Urgh. The Samsonite doesn't have that failure mode.