Husker Du pre-dated the Nirvana era but I reckon they inspired the sound (I think Novoselic was quoted as saying that Husker Du had done everything Nirvana did before they did it). Great band.
I was fortunate enough to see Bob Moulds last 2 visits to these shores for his own headline tours (I didn't see him support Foo Fighters).
Here's my review of the 2008 gig http://www.egigs.co.uk/index.php?a=12344
and here's my review of his Copper Blue tour earlier this year http://www.egigs.co.uk/index.php?a=14135
I'm afraid it's a bit gushy but I reckon Copper Blue is my favourite album of all time.
I'm really jealous of anyone who saw Senseless Things live, they're another favourite of mine.