I'm going to go ahead and be the guy that states the obvious. Porcupine Tree. Some others off the top of my head...Mastodon, 3, Tool.
Actually i did hear a band the other day called bigelf. Not too shabby. but i didnt get a good listen to the track.
It depends really what you mean by 'prog rock' I guess, so it is hard to put a finger on what exactly you are after.
Give this one a try: Demians ~ Building an Empire It's a one man project und quite interesting I think, quite proggy but in a modern way. Here is an example: [ame=http://www.youtube.com/watch?v=82QgATnfwxE&feature=related]Demians ~ Empire[/ame] I think Demians are awesome.
Black Bonzo! Agree with Ken on Nektar, but their best stuff is not exactly current. "A Tab in the Ocean" is a seriously awesome album. EDIT: and if you're interested in prog in general, you need to check out this monumental thread of prog goodness, maybe the best thread here ever: http://www.ultimatemetal.com/forum/non-opeth-music-chat/150277-rare-prog-early-70s.html I shall also bump it for good measure.
If you are talking about the bands trying to recreate King Crimson and Camel sound and add something to it to make it unique, I would say Mastodon's Crack the Skye beats them all. You might like Cynic, too, although their latest album called Traced in Air didn't sit well with me. People swear by this band, so you might want to check it out. There is this band called Three that does a pretty decent job, but their songs are hit and miss. You may want to check out The End is Begun. And the Mars Volta has a lot of that type of stuff in their music - you might like them as well. If you're referring to prog rock as a wider term of bands using multi-layered music to span anything between Pink Floyd and Metallica's Master of Puppets, I will re-state the obvious and say Porcupine Tree - they have such a huge range in their sound, so I would listen to parts of different albums. Marillion is pretty good too - you may enjoy Marbles.
Forgas Band Phenomena Taal Hammers of Misfortune IZZ Karcius Karmakanic Little Atlas Magic Pie Muse Naikaku OSI Overhead Paatos Phideaux The Season Standard Tangent Wolverine - Still (Their other stuff is more metal) Ozeric Tentacles Neal Morse Spock's Beard Flower Kings
What people have said, and also: Beardfish Pineapple Thief Riverside Blackfield, No-Man, and Steven Wilson's solo work Pain of Salvation, if you can get past the cheese (ie, if you like crap like Dream Theater)
