Pitch-shifting streaming audio?

I want to be able to change just the pitch of songs in real time (not recorded tracks) for YouTube karaoke. This can be done using an app like Audio Hijack with a pitch-shifter plug-in, but that seems like expensive and complicated overkill for just the one effect. I have come across an application for the Chrome browser called Transpose pitch>speed>loop that supposedly does this, but I would have to install Chrome on my MacBook. Has anyone had experience with this application or other similar ones that might work for me?