Soundgarden: taken from a piece of art they saw standing in a town square somewhere
Smashing Pumpkins: just the dumbest jokey name they could think of
Metallica: a name a friend of Lars Ulrich came up with. Also the name of a magazine around the same time.
NickelBack: one of the members ( I forget which) worked in a Starbucks or some similar place, where the most popular coffe cost $1.95. People would always pay $2 so he’d always have to give them five cents (a nickel) back.
Dave Matthews Band: Duuuuuuuuuuurrrrrrrrrr….. <img>