BoC needs some documentation, but contains lots of usefull stuff like

• EventAggregator pattern implementation
• Inversion of Control wrapper (although being an anti-pattern, still very usefull. see other BoC packages like BoC.InversionOfControl.Unity for implementations)
• UnitOfWork pattern implementation (see other BoC packages like BoC.Persistence.NHibernate for implementations)
• Bootstrapper and Background task pattern implementation
• Logging wrapper (see BoC.Logging.log4net for implementation)
• Persistence repository and service pattern implementation (see other BoC packages like BoC.Persistence.NHibernate for implementations)

#BoC and Sitecore If you would like to get started with the BoC and Sitecore, follow this excellent tutorial by Guido van Tricht: http://guidovtricht.nl/2015/07/sitecore-mvc-musicstore-part-1/