I think it’s blooming great that with a single-line command I can turn my mini iMac TFT Pi into a photo frame for displaying slideshows with the images autosized for the display.
Install the frame buffer image library (fbi) then use the fbi command as detailed by Jamie Jackson on his excellent blog: blog.jacobean.net
Load up the folder of pictures (png format in my case), pop the single line command into a shell script, editing the parameters to suit (path to images, image type, time in seconds to show each pic), save the .sh file into your Desktop folder and give it the right permissions, and you can click it to run. A keypress will terminate it.
Update: I haven’t used it but apparently there is also an improved version of fbi called fim with more keyboard commands to let you manipulate displayed images . There’s some info here: www.raspberrypi-spy.co.uk