I seldom used portrait orientation when taking photos until a couple of months ago. Now I seem to be doing it regularly! I may have started turning my camera in my bathroom “studio” to avoid getting towels and bathroom fixtures in the shot, but then I continue to use it- especially when I want a shallow depth of field in front of, as well as behind, my subject. My 50mm lens does this beautifully, as well as my 85mm macro lens. I would love to own a LensBaby some day to play with moving the focus around! I did order one for my iPhone (coming in August through the kickstarter deal), which will partially satisfy my desire for this cool lens.
Here are two shots with a vertical (portrait) orientation. The first was taken with the macro lens. I took the photo with both orientations, and liked the vertical one best (those blurry berries in the background and a small unfocused slice in the front). There is some texture added to this image (a bluish one from Kim Klassen- teal?).
The one below was taken with my 50mm at 1.4 to give a very narrow field of focus- with lots of blur in the front. It was actually taken for a Be Still 52 lesson on side lighting. The cup was placed on the floor by the open front door (on the left for light)- with a piece of white foam board for a background. There is also a bit of lighting coming from the patio door farther away on the right. I used my Warm Black and White preset (some split toning) for the black and white conversion.