Not necessarily free though, now is it? How much fuel would someone burn up to angle themselves right to get to Mun? I\'m not well-practiced in that department, myself, so I\'d use up way too much fuel maneuevering for a Munar obrit...
Come on, don\'t go off topic with your 'last person to post' spam. ;P My favorite modification is probably C7 as well, while my second favorite is either Down Under or NovaPunch - I just got NovaPunch and need to test it some more.
Windows machines can get you double the performance for half the price, though - with none of the software limitations of Mac computers (although those are slowly disappearing).
I just threw it into the original part folder. Which may or may not have something to do with the fact that these engines only fire backwards for me, regardless of which part I use or where and how I place it, effectively crashing my plane on the launch pad.