There are quite a few companies that run with an 'unconventional' management structure. A recent link on HN was to a HBR study about Morning Star, a mature company that has run with a 'no managers' strategy for years.
Valve is run more like a FOSS project with no official hierarchy. Holocracy is about refactoring the traditional org chart into a more task-based model. Brian Robertson, one of the guys who started the concept, explains the differences here:
http://holacracy.org/blog/whats-wrong-with-your-organization...
'Maverick', by Ricardo Semler, was written in 1988 and is well known among business types: