I've been up in Seattle this last week doing the Remote Medical WFR course, and we had a day off yesterday. Since I'm still planning a Three Sisters trip sometime soon, I decided to go for a hike up Mt. Si, which simulates a reasonably grueling approach. Little bit of excitement after reaching the haystack basin, a twin engine Cessna zoomed over us only about 50' off the summit. Don't know if he was buzzing some people who did the haystack scramble or just saw a mountain all of a sudden when the clouds broke!