just a quick one: this coming weekend will see the gallery weekend, meaning lots of openings and extended opening times for most major galleries. definitely one of the best chances for an evening of gallery-hopping with lots of discoveries to be made. buy a day pass for public transport or go by bike to make the most of this event - venues lie across the city, mostly in mitte and on heidestraße (near hauptbahnhof).
if you happen to be in mitte and need a break in between, have a pizza at clärchen's ballhaus - with this weather and a bit of luck you could sit outside and watch the crowd go by.
oh, and before i forget: on saturday, 2 may, KW (kunstwerke) will hold their opening night. certainly not to be missed! more info here.