DREUPELKOT http://www.dreupelkot.be/
No beer, but you must visit! It may not be the smallest, but it sure is the most peculiar Belgian geneva-café in whole Flanders and surrounding areas. Watch out for Pol, the owner. He looks a bit untidy at first, but once he starts joking, he is rather nice really.
If he's sleeping in his armchair, wake him up carefully, you never know...