If you hike the trails in Glacier National Park, you are frequently treated to some isolated, breath-taking scenes.  Here, the nearby mountains blocked all wind, creating a mirrored surface which was only disturbed by a trout feeding just beyond my fly casting distance (actually, trying to get that "extra" length to my cast, I did an impressive job tangling my fly line in the branches of no less than three trees behind me!).

In a reflection photo like this, I abandon the rule of thirds and move the horizon near the middle.  The lines of the near mountains on the left and right both provide strong leading lines to the center.  The reflection in the water is interesting as well - in establishing the depth of field for this photo (near, middle, distant) - it is the refection of the distant sky in the water which serves as the foreground.  The brain "knows" the sky is far away, so do you see the cloud reflected in the water as being close or far away?  Or both?