Biking to the airport / leaving a bike for a week I'd like to try riding to the airport or to public transit when I travel. Does anybody do this? Any suggestions for how to secure a bike if you're going to need to leave it for a week or so?
This isn't uncommon in our neck of the woods. If you're a light packer, taking your bike the the airport can be a huge money saver.

If your airport doesn't have a bike locker, bring two trusty u-locks with you. Use one u-lock to secure your front wheel and down-tube to one pole, and the other u-lock secure your rear wheel to another pole (please, never use a cable lock unless you're hoping to file an insurance claim for your bike when you get back into town). Try not to use your favorite bike if you have more than one.

Either leave fancy accessories and lights at home or take them off and take them with you when you arrive at the airport.

If your seat post uses a quick release, I would recommend replacing it with a bolt-on clamp. This won't guarantee your seat (or other bolted on parts) is safe from a well prepared perpetrator, but the majority thieves are looking for a quick and easy score, and will skip over your well-secured components in favor of lower hanging fruit.

(photo borrowed from lifehacker)