"If your company is like most, you probably have a PC graveyard
filled with old systems that are too slow to run the latest
versions of Windows. However, before you ship those systems off to
technology recycling centers or give them away to employees, you
should consider one possible way to reuse them: Turn them into
Linux firewalls.
"Many of these old PCs can easily run Linux, which requires less
system resources than Windows. With a few hardware modifications,
they can be turned into solid, reliable firewalls. These firewalls
can be used to segment certain departments (such as accounting)
from the rest of the network, or they can be used in remote offices
and/or for telecommuters. Small businesses may even find that a
Linux firewall can serve them well as their primary means of
sharing Internet access and staying protected from Internet
attackers..."
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