German Apothekes | Deutsche Apotheken by anacapa
I just read mccrorj's local custom tip for apotheke's in Berlin. I wanted to add that every pharmacy posts a list of which pharmacy is on call. You can go to your nearest pharmacy, check the list in the window and find out which one in the neighborhood is open. Pharmacies at major train stations in Berlin stay open longer than your average pharmacy, so if it's before 8pm, you might be in luck there.
Also, note, grocery stores do not sell aspirin/bandages/tampons and the like. Best bet is to go to a drug store, a Drogerei, not an Apotheke, for these things. There are lots of these around, my favorite being at the various large train stations...(Zoo, Friedrichstrasse, Hauptbahnhof)