Sometimes, your photos just look a bit dull. It's not that the subject matter isn't interesting, it's that the lighting just didn't work out right. Especially if you use the inbuilt flash on your camera - often background areas turn out too dark, and this detracts from the overall image.

This tutorial gives you a nice, easy way to brighten up the darker areas - of course, if you've over-exposed a section of your photo, the exact same technique should work.

Remember, however, that no amount of photoshopping can add detail that the camera wasn't able to capture in the first place (like in the ugly phone-cam picture of my fiend here). If a section of your photo is so dark it's nothing but black, or so over-exposed that it's just a white glare, then the camera never captured the details you're looking for in the first place