Viewing a man page in Preview.app

Macintosh OS X command line to format a "man" page and open in the Preview application

groff -man /usr/local/git/man/man1/git-config.1 | open -a Preview.app -f

Update: Using the man -path argument you can further enhance the command line, eg

groff -man $(man --path git-config) | open -a Preview.app -f