[CentOS] Ham Radio s/w and CentOS? {including Echolink}

I am going to present Linux to my ham radio club at some point in the next few months, and wanted to collect info on ham radio software, including options for echolink. Our repeater has an echolink connection, thus if I present the software available for it, it might perk up people's interests more.

It would also be very helpful if the echlink applications offered proxy/firewall options so people at companies or at home that have networks that implement firewalls, can proxy out and still get on Echolink.

Also, anyone know of a live-on-CD/DVD CentOS distribution that may include Echolink and/or other ham software?

Thanks for any leads.

Scott, WY1Z