A38 is the former Ukrainian barge Artemovsk 38, which became after reconstruction one of the coolest clubs in Budapest.
On the deck there is a restaurant and a terrace (closed in winter), and in the hold there is a dance floor. A38 is a venue for designers, artists and open-minded persons. Definitely worth visiting despite the above average prices.
Buda side of the Danube, 150 m south of Petőfi Bridge.
Link to website
Places in Budapest
Have been there! Satisfied.