Nirvana might have influenced tons of shit bands, but I can't really think of another rock band that filled the gap between mainstream and underground music like them ever since. Some might mention Sonic Youth, another tremendously influential band that signed a contract with a major just before Nirvana, yet they never managed to reach their level of popularity or have been truly assimilated in popular culture to that extent. Anyway, great band, even though I don't happen to listen to them often anymore.
To the poster who said that only Lydon liked Abba in the Sex Pistols: not really, all of them occasinally used to frequent gay discos at the time, and Abba were most certainly a band popular in those places, as well as the UK charts.