Secure servers for file-sharing, web applications, backup systems and firewalls.
Hosting for Cyclos is less straightforward since this requires a Java/Tomcat environment, but this can also be arranged, either using a specialized hosting service or via a co-hosting arrangement - in the latter case using either a Debian GNU/Linux server or an OpenBSD server (a costly option given that the Java environment has to be compiled from a patchwork of sources).
Heterogeneous networks: using Samba to provide a cost-effective and flexible file-/print-server for environments where MS Windows is still required for some purposes.
Robust systems built on new or re-used hardware: i386 or SPARC.
Secure networks networks: OpenSSH and OpenVPN.