I often find myself with a bunch of images that are not properly rotated. Many cameras write the rotation information to the EXIF header of the image file, but the file itself is not actually rotated. Some photo editors do this automagically when you import the files, but I prefer to copy files manually to my drive.
I therefore have a little one-liner that can rotate all the files in a folder:
find . *.jpg -exec jhead -autorot {} \;
It works recursively, and is very quick!