Alfred is currently my launcher of choice on Mac OS X. It can easily be customized by writing extensions. Of course, I couldn't help tinkering with it myself. To install an extension, simply download the file and open it. Alfred should take care of the rest.
This extension creates an alias (the mac-specific alias, not a symbolic link) to a specified file or folder. The newly created alias is also copied to the clipboard so that the file can be directly pasted in the Finder.
To use it, simply select a file or folder in Alfred and invoke the
alias action. An alias to the selection will be created on the desktop. Alternatively, just type
alias in Alfred followed by the name of a file or folder.