I've done a number of phone interviews. I honestly can't think of one that didn't result in a face to face interview. If any did it was probably one that I was just as happy to loose.
Typically when I get a phone interview its from the hiring manager. Typically a recruiter or Catbert type will call to do an initial screen. I usually don't consider that to be so much an interview as them confirming what's on your resume and maybe getting a little more detail so the hiring manager can make their decisions on who's the best bets for the "real" phone interview.
The most important things have already been mentioned, but I will point out that it is a good idea to know as you can about the company ahead of time so you can make intelligent comments about how your past experience relates to the work they do. Sometimes that takes a little effort if there's not an obvious link.
Definitely make sure there a minimum of distractions so you can think clearly and quickly. The phone interview that helped me land the job in Yakima required a lot of ability to concentrate so I made sure I was not going to be interrupted by my kids.
Relax enough to be natural but keep up your guard. There's reasonable chance that they'll throw you a curve-ball just to see how you handle it.
Never discuss money at such an early stage. If they bring it up avoid answering by saying things like "I'd rather wait until any offers are made to discuss that issue", or "I would expect an offer commensurate with my experience and education". If they ask what you're making right now, tell them or don't tell them, but don't let that distract from the guts of the interview.
I've had phone interviews that lasted for 2 minutes and for an entire hour. Sometimes it's just the hiring manager asking a few easy questions and then inviting you out for an on-site, sometimes it's a conference call with several other people bombarding you and it takes them a week to call back with an invite. And anything in between.
Do not chew bubble gum, eat popcorn, or drink beer while talking on the telephone.
Good advice but it might be a good idea to have a glass of water/juice or a cup of coffee/tea on hand. If you get a marathon session you'll need to be able to wet your throat on occasion. Just make sure you don't slurp. Nothing carbonated though. Belching on a phone interview is bad ju-ju.
Avoid talking about your personal interests, especially those that relate to hunting/shooting/fishing. If anything spin it as hiking and camping. You never know if the interviewer is a PETA type or a Ted Nugent fan. If the former talking about that will quickly end the interview, but avoiding it won't hurt with the latter.
Good luck.