For the one of you who may be considering a run down the Aniakchak, be advised there was a large landslide in The Gates which has rendered this section of river unrunnable (except for maybe a chosen few). It can be portaged around with much effort.
Interesting. A friend was talking about doing that. Incredible area, but a lot of expensive faffing to get there and back out unless you plan to walk between Port Heiden and Chignik and just use the mail plane.
I was there in July. Interesting place but honestly I think there are lots of other more spectacular places in AK for the money (cuz it twernt cheap). The whitewater sections of the Aniakchak were fun but there was too much flatish/lazy water to recommend. Tons of bears though.