This free Mac application was originally produced by FontGear Inc. Unlauncher for Mac lies within System Tools, more precisely General.
From the developer:
When Unlauncher runs, it just looks for the HP Launcher volume on the Desktop. If it finds the volume, it immediately sends an "unmount" command, and then quits. Otherwise it does nothing.
The easiest way to install Unlauncher is to put it in your Utilities folder and then drag it into the Login Items list in the Users & Groups panel of your System Preferences window.