Spontaneously record musical ideas and create songs complete with drums and effects.  With guitar friendly features such as a unique Instant Drummer with professionally recorded drum sessions, 7 studio-quality effects, and community services like built-in online music collaboration and instant podcasting, RiffWorks is the most creative recording system ever produced.  Great for guitar players and any musician or singer wanting to record at home easily.  Works on Mac OS X Universal, Win XP and Vista. Requires an internet connection and an ASIO or Core Audio device for plugging your instrument into your computer.