A number of airlines do SEA-ANC, although all but Alaska only fly once a day-- most are red-eyes from ANC around 1:00am. I found flights on Delta, Continental, United, and American once a day, plus ridiculously frequent service on Alaska. Most showed a fare of $235 one way.
TWA flies ANC-PDX if you're looking for Aviator miles. Canada 3000 does ANC-YVR for $180 plus lots of tax.
[This message has been edited by Viajero Joven (edited 07-05-2000).]