Argh! Sylar! Out of my head!!
I only remember bits and pieces, but there was one nightmare scene that stuck. The dream was set sometime in the future; Peter had a cool anime scar down his face. Peter and Sylar where facing off and in the context of the dream they'd clearly thrown down before and knew exactly what each other was capable of, and most importantly how each other's powers worked.
Sylar had apparently been threatening people Peter cared about, and Peter was upset, understandably, but in the dream he was confident he'd covered all his bases.
Then Sylar laughed at him. "You shouldn't be so sure, Peter. I've learned a new trick."
"I don't care what new power you've stolen. You need to be locked up, and I'm gonna do it."
"Oh, I don't know," Sylar said. "I think you'll like this one." Then he went invisible.
Peter freaked the hell out and telekinetically threw Sylar against the wall. I don't remember all of the fight, but I know at one point Sylar was mocking Peter and asking if Peter knew what a heartbeat sounded like right before it stopped. And I'm pretty sure he was mimicking Claude's accent, at one point.
Okay, subconscious? You can go right back to those nice Peter/Isaac dreams any time. No more Sylar in my brain, murdering my favorite characters.