Photoshop is the alpha and omega of photo editing apps, but every once in awhile someone comes up with a way to do a specific function even better than Adobe.
A case in point is PhotoScissors, a US$19.99 Mac app that makes it easy to remove an object from a photo, then paste it in somewhere else. This can be done in Photoshop, and I marvel watching pros do this. It takes more than a few steps, and can involve the Photoshop Magic Wand or the Quick Selection Tool.
PhotoScissors works differently. Take your photo, and paint some broad green strokes on what you want to preserve. A remove tool is used to paint red on objects you want to remove. You often want to remove a background, while you want to preserve a foreground object or person. The app does a quick smart analysis of what is highlighted, and quickly gets rid of the unwanted background.
There are lots of reasons to have a tool like this: product photos, separating objects from a background, creating an isolated image with a new background, etc...
I tried the app on a variety of photos, and it worked well. It's not always perfect, but with a little effort you can clean up anything that is missing in the cutout. PhotoScissors is often faster than any other method I've used, including Photoshop.
PhotoScissors isn't a replacement for Photoshop or other high-end editors -- it just makes cutouts easy. There are tools to zoom, undo, and change background color, as well as controls to change the size of the brush. Help is built in, although it is pretty basic.
On some objects, I found the Photoshop Quick Select tool just as effective and quicker, other times PhotoScissors was more efficient. If the foreground and background object have similar colors, PhotoScissors will confuse them, but it is easy to clean up and re-render.
PhotoScissors is a tool for someone who spends a lot of time cutting out objects to separate them from a background. At $19.99 it is a lot cheaper than Photoshop, but of course the app is a one-trick pony. If it's a trick you need, PhotoScissors is a worthwhile investment.
PhotoScissor is not in the Mac app store, but you can buy it direct online. You can also download a demo version and see if it works for you. The app requires an Intel Mac running OS X Lion or later, with a 1 GHz processor, and at least 256 MB of RAM.