[CentOS] question about network repositories

Hi

I'm thinking about setting up a local / LAN respository for my CentOS, 
and probably other (Fedora Core) disto's, but have never done it before, 
so here's some questions:

If I setup a repository, can it hold different distro's / architectures 
& versions? Say for example, CentOS 4 (i386 & x64), CentOS 5.0 & 5.1 
(i386 & x64) - will each one have it's own folder?
Will it also be possible to only download the packages that are needed, 
instead of the whole 4GB repository from the upstream provider? I have 
some of the CD's or DVD's for all of the distro's, so really only need a 
few packages now and then, and instead of getting them from the net 
everytime, get them from the LAN repository?

Then, how would I do this?

-- 

Kind Regards
Rudi Ahlers
CEO, SoftDux

Web:   http://www.SoftDux.com
Check out my technical blog, http://blog.softdux.com for Linux or other technical stuff, or visit http://www.WebHostingTalk.co.za for Web Hosting stugg