When I started practicing seriously, I was studying with a dude who was totally obsessed (and still is, to the point of confounding himself with him) with John Petrucci.
One good thing I have learned though and I remembered, so I thought it would be of great use to everyone, would be his advice regarding picking direction:
When you learn a lick involving picking, practice it starting with a down stroke and continuing accordingly and after that, start with an upstroke and continue accordingly. This will not only develop great alternate picking flexibility, but it will also be a means of saving oneself in the middle of a song onstage, when a mistake is made and the picking direction is altered - the chances of picking things up from the point in which the mistake was made, will greatly increase.
Have you guys ever tried this? Does it feel awkward?