After I transferred my photos from camera to laptop a while ago, I noticed something odd about them. Many of them were over-exposed, while just as many were under-exposed.
After much fiddling and confusion on my part, I finally figured out that I inadvertently pressed the "bracket" (Auto Bracket) button. This means the camera is assuming you will take three shots in a row of the same subject, and each one will go from light to dark, and then you're supposed to go to photoshop and blend them together for an HDR type photo.
But I didn't do that, I just went on my merry way, snapping anything that took my fancy in the park up on our mountain. So some shots looked bleached out and others looked vivid and other worldly.
But once I got over my panic of not knowing what I did (and I fixed it) I kind of liked the shots. Note that these were taken within minutes of each other in almost the same spot.