Oxygen Cloud is another player in the mobile access to files category with some cool value-adds. Integration with EMC Atmos, Isilon, VNX - can edit from mobile platforms (depending on type / apps), synchronization as you'd expect, and . . . on-premises AD/LDAP integration (sweet). Centralized management for policies - good enterprise tool that is worth checking out.
Interview with Lucas Welch, Dir of Communications from Opscode - http://en.community.dell.com/techcenter/b/techcenter/archive/2013/03/12/chef-11-interview-with-lucas-welch-director-of-communications-at-opscode.aspx