Play with manual. Watch the background sharpness change with aperture adjustments. The SimCam: Film and Digital Camera Simulator - Photonhead.com
interesting idea, seems to work pretty well to. I didn't play with it for too long but I can definitely see it being useful since it teaches the basics of photography without actually requiring having a camera and knowledge of how to change all those settings. Nothings like real experience out on the field, though
