When the T1 goes in (currently scheduled for Tuesday, crossed fingers!) the router will be installed in the basement. I will need to decide how to run networking from there on to our computers.
Right now we have the Wildblue modem going into my Linksys wireless/wired router in the living room, and all computers connecting on to that. The simplest solution with the T1 would be to let the T1 router just replace the Wildblue modem. I'd have to run one cable from the basement to where the Linksys router is, and then the Linksys would be a client of the T1 router, and all my PCs would be clients of the Linksys. This would be easy to install and require minimal configuration changes. We could be up and running very quickly. And it preserves having the wireless part of the network which my laptop and both of our Eees use. In addition, it means we're all still protected by the integral firewall in the Linksys.
The only disadvantage to it, though, is that it means we have two routers in between each computer and the Internet. This not only means two points of failure and two (very minor) latencies, it also makes certain kinds of port forwarding complex. Those are very minor concerns, and do not seem to come anywhere near outweighing the pros of this approach. But it feels like, if I were to start from scratch, I would never design a network with two stacked routers, so evolving to that is a bad idea. (What I would probably do is have a router which included the wireless and firewall functionality I want, but also had a T1 DSU/CSU. But since I can't put those functions all into one router, I have to have two stacked.)
So one thing I plan to do today is see if I have a long enough network cable, and if so, run it between the two router locations, so it'll all be ready when the T1 goes in. That way, once we know the T1 works, I can switch us to it immediately, hopefully. That'll get the majority of our stuff up and running. Later, I can go back and configure port forwarding on the T1 router to mirror the forwarding on the Linksys, so that requests from outside go to the right place (notably my HomeSeer system and my MUD development system which I access from outside).
But maybe one day I'll reconsider this and put some systems inside the T1 router but outside the wireless router. Or not. I'm torn on the subject.