Wirelessly posted (iPhone: Mozilla/5.0 (iPhone; CPU iPhone OS 5_1_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9B206 Safari/7534.48.3)
Horizon flies hourly shuttles between Seattle and Spokane. Anyone (not just AS golds) can do same day standby for free on that route too so it is really convenient. The Q400s aren't bad for those short flights either.
WN never really had a great schedule on that route but the few times I flew GEG-SEA/PDX the planes were packed. Both of these routes were inherited from Morris Air, so they've been around for a while.