The easiest, least expensive way to begin using Untangle Next Generation Firewall (aside from using a virtual machine) is to simply repurpose an existing computer. While virtually any used PC or server can be used with Untangle, some work better than others.
A repurposed machine should meet the following minimum requirements, assuming a relatively small workload (10 to 15 users with average utilization):
Intel Pentium 4, Intel Atom, or equivalent processor
1 GB RAM
80 GB hard drive
The ability to support at least ...