HOPEFULLY if you like beatboxing you already know Rahzel so I won't post his stuff... if you don't know go find him.
Check this guy, my favorite beatbox stuff right now... the beatboxin' flute playin' guy. Badass...
http://www.youtube.com/watch?v=c6SHsF1n9Qw
http://www.youtube.com/watch?v=meR5nk8WaLE
Check out his other videos on there too.