I'm catching a very early flight from Basel that's so early that it's not worth going to bed really. Can any of the Basel locals recommend a pub or bar that is open until 4a.m.-ish where I could hang out?

Either in the airport itself or in central Basel.

We used to go to InterPub on Steinentorstrasse, just opposite Paddy's and down a bit, after the clubs had chucked out.

Theres also the Night Cafe attached to the old Warteck bar by Messeplatz.

I've never been but I think the Grand Casino right next to the airport is open until early morning.

And handy for the bus too #50 stops right outside

And you can park free of charge in the white boxes there, I always do & 1 bus stop to the airport!