Sud des Alpes in Geneva, the club that belongs to the AMR (http://www.amr-geneve.ch/
) has excellent if at times quite hermetic stuff. They also organise a festival in the Parc des Cropettes just behind the train station.
You can check out Geneva's oldest squat, Ilot 13, a buzzing little place with a nice bar serving cheap food. Another squat, Cave 12, has regular shows (http://www.cave12.org/
) and you can also try the Rhino squat, I saw there some Bulgarian woman choir in the 90's that ended up semi-famous (Mystere des voix Bulgares).
Le Chat Noir is a cabaret bar in Carouge that has a good choice of jazz and blues, often with a twist.
Otherwise Fetes de la Musique in Geneva (orgnanised on the nearest week-end to the official start of summer, on the 21st of June) has countless music stands dotted all over the city.
That aside, there is nothing to do in Geneva...