On the bank of the river Aare you will find this nice bar/restaurant which used to be the old slaughterhouse of the town. But don't be afraid to go there, nothing reminds of the ancient times.
http://solheure.ch
Well known concert venue located a little bit outside of the old town - but still reachable by foot. Check their lineups on the website. Even international bands go there for a gig.
http://kofmehl.net