Many Static Pages Across Various Domains

Alright, what would be the best practice for this?:

I have several domains, like
www.ryankopf.com
www.cmuscatine.com
www.aiowa.com

Some have lots of static pages (first two) but others are more dynamic
(picture gallery on the third one). I am working on re-implementing
them in RoR on my GoDaddy apache shared hosting server.

I want to have just one ruby application, because I have features that
I'm going to want to use across the board... but I'm trying to figure
out the best way to do this.

It was suggested just to create a static.rb controller, then in views/
static/ put the pages as .rhtml. Then I would use apache's mod_rewrite
or something like that to direct www.ryankopf.com/ryan_kopf_static/page.html
to the RoR program. But I have layouts in place on each site, and each
is different, so wouldn't I have to create a new controller for each
website? (I use just one file for the layout so that I can easily
change it). What's the don't-repeat-yourself method of doing this?

You can specify a layout when you render an action, so you could have a
single controller.

   render :action => 'whatever', :layout => 'layout1'

Okay. Is there a way I can figure out which domain is calling? Then I
could get really simple and define a Website model. The attributes
would be
:layout - >name of layout
:pagename - > page file location
(example :homepage -> "/views/Website/ryankopf/homepage.txt")

Is that in the environment somewhere maybe?