rumblings here in Idaho too
just a couple times in the past 2 days. Like a low roaring large plane or thunder, but lasting much longer than any thunder I've ever heard. Otherwise we are in a very quiet period, no rain, storms, etc.
Before the tsunami there was a nearly constant buzzing in my ears building up over a couple of weeks - it was really loud outside - like the roaring of thousands of bullfrogs but at a high pitch. Curiously, my husband, who doesn't hear in the higher registers, didn't hear a thing. Inside I didn't hear it until the last three or so nights before the Ts. hit = but the night before the tsunami hit I was kept up at night, in bed, with the sound so LOUD! Decided to go to the doctor and see if I had developed tinnitus like my Mom did at my age. Then it just dissapeared. It returned only slightly, only when it was still (no traffic) and only outside. Last night NOTHING, quiet on a quiet night. Just like it should be. Maybe we're just seeing and hearing the earth settling after the big quake. Living in a quiet, semi-rural area we can pick up more of this which would just be drowned out in the city.
The one thing that is new is that this is the very first time we've been able to compare notes on it. I probably wouldn't have connected the sounds to the tsunami if so many hadn't mentioned their own experiences.