I'm using Ubuntu 12.10, and some applications have two launcher icons in the Unity launcher. There is one smaller, pixelated icon, and one regular one. It only happens with some apps though, but not with others (for example, it happens with Chrome, but not with Firefox), for some reason. See this imgur album for screenshots.
As far as I can tell they both perform the same function, so I have no idea why there's two copies there. I'm guessing there's second directory somewhere containing a bunch of copies of the binaries for the apps on my system, or there's a directory full of symlinks somewhere. The larger icons (or maybe both, I'm not sure) are probably pointing to
/usr/bin, but how can I tell where the smaller ones are pointing to?