Inexpensive Network Servers?

Linuxthess asks: "I work in a small company with only 20 or so employees. Being the most tech-savvy of them I find myself doing less work as a salesman, and more as their non-paid tech support. I was asked for a solution to create a domain for login authentication, a DHCP server, a webserver, file & printer services, and e-mail. I found three such companies with an inexpensive, yet solid products aimed at what we need: one is Celestix with their Aries and Taurus products; there is a company in Chicago called Dartek which sell a custom-built box called iMass which comes in three flavors; and lastly a company in Canada named Net Integration Technologies Inc who has a box named Net Integrator that is available in various flavors. Does anyone have experience in regard to these solutions? I think we will go along with the Taurus, but I want to hear a little more regarding the quality of doing this job inexpensively (these things start from $800 and go until $3000). I spoke with a tech-support guy, and he told me customers buy a couple of these since they're so cheap for redundancy, and clustering."