Mainstream, but classics You might actually like the album 'With Teeth', that's the most mainstream thing he's done since Pretty Hate Machine, everything else is much more experimental. My gf HATED NIN, and she listened to a lot of great music I didn't even know about, so i've come to accept that it's not everyone's bag.
I was a big fan of Trent's from a young age, he's the guy that inspired me to toy around with synths. If you took the time to listen to his main albums, i'm sure you'd find a lot more to like, and even an appreciation for his music since he's one of the most talented musicians around on a technical level. I outgrew almost all of my childhood bands, but this is one of the few exceptions.