Sportify for OSX:
I'm shocked that there's no keyboard shortcut for rewind / fast forward a song, on a great app like this one. There might be some strange reason why Spotify decided not to implement or activate it.
The shortcut "cmd+opt+left/right" seems to be available (which is the same on iTunes, and for some weird reason doesn't work very well for me).
Though I prefer simpler ones, like just the left and right arrows (like YouTube). That would be awesome.