I listen to some punk bands that may attract the prog ear. I've mentioned "Rx Bandits" many times but many people have not responded to them. They are a fast driven reggae type band that experiments with times and has some very clever lyrics. Though they are not prog they are one of my favorite bands. They have one guitar player, drummer, an alto/tenor sax, keyboard, and other various cameo horns. Another band (though tending a little towards metal) is "thrice". Their lyrics are incredible and the music is very cool with some nice time changes and instrumentation. Those are the best two I can name for you as most punk bands don't care much for talent or experimenting.
If your into a more hardcore approach I would recommend "Refused" (though they broke up) they came out with an album "The Shape of Punk to Come" in 1998 that was really pushing the borders (especially to the standard "punk"s eyes.) They do a lot of cool time changes, have some part by part songs and lyrics that deal with a revolution, peace, and the equality of humanity.
But overall, check out Rx. The album to check out would be "The Resignation" since the other albums are less instrumentational and not as well written. They have also said that their new album (coming out in November) will be far more musically advanced and will lean towards "pushing the boundaries of modern music" so I am extremely pumped for that. Thrice has also anounced that their new album will be their style of punk (very instrumentally invovled with changing signatures and poetic lyrics) will be more blues and jazz driven, which will be a surprise that I am waiting for.
Overall I feel like thrice and Rx Bandits (especially) are going to evolve into the newer sounds of modern prog without being heavily prog influenced in their backgrounds. This is what will make them unique and separate them from the progressive bands that we are used to hearing. A lot of my friends that listen to prog think I'm crazy for saying it, but these bands that grew up in the punk and ska/reggae scene IMO will be the new bearers of a new style of prog.
Thanks Bartok for the interesting topic. Theres been enough punk bashing without the time to experiment the small minority of impressive bands in the genre.