I'm sorry if this disappoints you. I use network-config program to manage multiple network configurations on my debian laptop. The program uses its own configuration and applies the network setting directly with ifconfig. So I think it works for all distros or *nix types.
in reply to Changing IP address on linux box
I work interchangeably at two offices (of the same company), both use wifi connection. At home, I use ADSL connection. Having all my configs done correctly, all I do each time I switch work place (and thus network connection) is fire up the network-config program, choose a suitable network profile, click the apply button, and I'm connected. BTW, it's written in Perl with Gtk2 for its nice and simple GUI.
Open source softwares? Share and enjoy. Make profit from them if you can. Yet, share and enjoy!