FxCamera is an app with different type of effects to take photos in.
There's the ToyCam effect, which adds cross-process emulation colour over the image. You can set different colour modes to take the photo in, such as a green, blue or yellow emulation, or a vivid green or red, and a couple of high contrast modes. I think this is probably the best effect in the app as you can get some really nice photos with it.
Another effect is Polandroid (I thought that's quite a clever name adding Android in), but that's simply just a Polaroid camera effect. A cool effect if you like the old Polaroid camera photos.
There's also Fisheye, which adds an effect that the image is rounded like the end of a camera lense, but it's not very well done in FxCamera, but that might explain why this effect is still in beta.
SymmetriCam is pretty self explanatory. It just creates a symmetric photo of what you've taken, and the last effect is Warhol, which creates a Warhol style photo (the photo with four of the same photos on in different colour hues).
The app also has a normal camera on, which lets you add some filters such as monotone, sepia, negative, posterize and solarize, just like you'd find on most digital cameras.
The app is free, and can be found on the Market by searching for FxCamera, or scan the QR code below with your phone to open Market URL, or use Chrome-to-Phone to send the Market URL straight to your phone (right click on the URL and Chrome-to-Phone).
FxCamera Market URL