Sometimes, you just have to take a picture of what's in front of you but you're stuck with low light and a mobile phone camera. Free utility Unshake makes those photos somewhat presentable by toning down the blur.
You can't truly make a blurry photo clear (the only thing you can do is breathe like a sniper when you first take the photo), but you can at least salvage some of it with this handy program. Unshake can really make your photos passable, but it takes a bit of tweaking. There are a number of settings that you'll have to play around with to find the right balance—the wrong combination can produce super etched-looking photos—but with a bit of patience, you can probably turn a trash-bound jpeg into a photo worthy of at least showing your friends. Take a look at the photos below, the first being the original and the second being Unshake's output:
Original photo by Aoife city womanchile.
It certainly isn't flawless, but this is with minimal tweaking, and the cat's face looks quite a bit better already. Unshake is in Java so it is available for all platforms, but keep in mind that also makes it a bit slow, and you won't want to work with full-res pictures at first. Copy the photo you want to tweak, bring the copy down to a smaller size, find the settings you need in Unshake to make it look good, and then apply those settings to the original version. Then go make some tea, because it'll take a few minutes before anything useful pops out.
Unshake is a free download for all platforms.