The best time to fly, as I re-discover every year, is decidedly NOT during Christmas. This year, however, I decided to get a little more savvy about the proceedings. Plus, I'm planning a trip to Vegas, so I needed to re-evaluate ways to work the system.
For the past few years, I've relied almost exclusively on Orbitz, sometimes comparing it against Travelocity and Expedia. They end up with pretty similar fares, so I usually stick to Orbitz. The only catch is that you can sometimes get cheaper fares direct from the airline websites, and budget carriers like Southwest and JetBlue aren't even included the aggregate searches (sidenote: I'm still undecided if this helps or hurts them in the long run)... So when I know a route is covered by these carriers, I also look it up on their sites (sidenote 2: maybe travel agents could somehow use this to their advantage, and offer services to find you the best deals on the myriad of non-aggregated carriers).
Anyway, this year I tried out Kayak.com, the newest of the online travel booking websites, which searches all the travel sites -- Orbitz and the individual carriers included. Overall, Iike the no-frills presentation (a-la Goolge),
which also has great tools in the left sidebar to slice and dice your
flight options after your initial search.
Paired with the historical pricing and future prediction information on Farecast, it almost makes me think I understand how airlines set their fares (other contenders for this feature were FareCompare that has a clunky interface, and FlySpy that is still only out of Minneapolis) to see details about ticket price trends over time.
Finally, both during the booking process and while I was traveling, I relied on FlightStats to check routes, track flights and generally get the 411 on PDX. You can also check your current flight status from your mobile phone, which is pretty cool.

