Another hefty expense and technician time-suck is the company phone system. Instead of plunking down several thousand dollars for an internal phone system -- also known as a private branch exchange, or PBX -- some small and midsize companies are opting for so-called virtual PBX services.

These phone providers, such as GotVMail, RingCentral, Packet8, Virtual-PBX, and many others, offer hosted phone systems that don't require installing or maintaining equipment. For a monthly fee of about $2 to $15 per extension, companies get an internal phone system with a main number, voice mail, and free internal calling. Incoming calls to an extension can be routed to a landline, VoIP phone, or cell phone. Because the equipment is managed off-site by the virtual PBX service, companies avoid paying a staff technician. However, many of the services are geared toward companies with fewer than 100 employees.

Some virtual PBX providers, such as Junction Networks and CallTower, also offer hosted VoIP plans that can lower long-distance bills without the cost of installing and managing an internal VoIP system.