I'm not sure what I keep doing, but every once in a while when I turn on my iPhone 3G (after turning it off completely, i.e., a restart/reboot) I see a couple of different weird "error" messages. The first error message says, "Slide for emergency", and looks like this:
Every once in a while someone will give me a large collection of images (JPG, PNG, GIF) that I need to either look at or print. On the Mac (and recent versions of Windows) there are now tools to look at a group of images, but I still like a little program that I wrote.
I wrote this program in Ruby, and what it lets you do is combine all of your pictures into one web page. Then, with the use of CSS, the HTML document you create lets you print each image on a separate page.