Sunset on Mount Rainier, shot from trailside above Sunrise (on the mountain's northeast side). This was the shot that convinced me that it's probably best to catch The Mountain just before sunrise or after sunset--it's so bright that it's really tough to capture well in the direct light of daytime, and of course a glowing pink sky makes for excellent light.

Sunset at Great Sand Dunes National Park, Colorado

Mt. Sneffels and turning aspens along County Road 5 near Ridgway, Colorado. My brother called this an "inverse sunset", with strong light on the foreground and the background in shadow.