Mac Minis would be fine as workhorse systems.

With a 2GHz quad-core i7 processor and 8 GB of RAM, this little box would keep up with most any business system on the market. Whatever isn't in the box can be hooked up to it through 4 USB 2.0 ports, one FireWire 800 port and/or one Intel Thunderbolt port. I think the latest Mac Mini is one slick little system.