Brezel Bar that has the best pretzels. They also make Brötchen (rolls) out of the same dough, and make Laugencroissants, plain or drizzled with white and milk chocolate. (Is your mouth watering yet?) I came here with Jessica, too, and she got little mini-pretzel pieces rolled in different seeds (sunflower seed, poppyseed, etc).
If you're in Berlin, they also have a good breakfast option, and it's a nice (but quite small) place to sit and read or have coffee.
Legend of the origin of the Brezel: A baker was challenged to bake a cake through which the sun shines three times: „Back einen Kuchen lieber Freund, durch den die Sonne dreimal scheint, dann wirst du nicht gehenkt, dein Leben sei dir frei geschenkt.“