A tip for Photoshop users: here's a nice action for brightening bad pictures, especially backlit photos with a blue or gray tint. It's the Sunshine Photoshop Actions set from Charmbox Studios. It contains six different actions for a variety of lighting effects. I bought it for $4.50 and it's been worth the money in time saved.
Kissed by the Sun is the most useful of this set, I think. Above is my fixed up photo.
Here's what it looked like before I ran the action:
Today I edited a few snapshots for a client. Here's the original image:
And here it is, sunnier:
I made a few minor tweaks after running the action to brighten the floor in the foreground, but the action got me pretty far.
If you're not familiar with an "action" in Photoshop, it's a series of pre-recorded steps. Instead of applying each step manually yourself (brighten, adjust levels, increase saturation, etc.), you simply click the "play" button in the Actions palette and they all happen in order instantly. A huge time-saver, and if the action is designed correctly, each adjustment layer is still editable so you can tweak effects as needed. For how to install a new action, see here. There are lots of freebies floating around the web, too. Anybody have some they swear by?
4/14/14 Update: You guys must have purchased a bunch of products, because I just got a note from Charm Box Studios. They'd like to offer a thank you! To get 30% off anything in the Charm Box Studios store, enter the code: CBS-loves-orange now through 4/30/14. One use per customer, no minimum purchase. Sweet.