I was told to ask on Server Fault when I asked on Super User, and that makes a lot of sense to me, so here it is.
I like the look of no www but am somewhat worried about drawbacks, such as shared cookies across the root and all subdomains (not that I actually know anything much about cookies at the moment, but I do want to futureproof).
My guess is this might possibly be possible through some sort of alias type thing. But I could be wrong, so here I ask.
Edit: I'm planning to host with NearlyFreeSpeech.NET. The server is Apache and I would guess the OS is some flavor of Linux.
Edit 2: So do you actually understand what I mean? What I'm looking for is this: when one browses to the site, http://foo.com/ is what they see in the address bar but http://www.foo.com/ is what is being accessed. I have to say Xorlev's answer looks the closest but will it work out, considering potential cookie issues and that I'm going to be using shared IP hosting.