Those flyers and album covers more than anything else are what warped my teenage mind and got me into punk music and culture.
That, and the fact that the punk chicks were the only ones that would give my nerdy ass the time of day.
His mere art is pretty damn great too, though. There was a big show of it in Chicago a while back...he completely covered the walls of a large multi-room exhibition space. It was pants-crappingly awesome and still the best art show I've seen in Chicago in the last 10 years.
I think it adds a lot to see it all together, presented like that.