Creating a RedHat based distribution

Hi,

I am considering creating my own little Linux distribution for use by me 
and my friends. I'm an intermediate linux user, and I would like to do 
this to enhance my knowledge of Linux, plus I think it's be a fun little 
project :-) I am most familiar with RedHat and YellowDog, so my obvious 
choice is to base my efforts off RedHat. Does anyone have any 
suggestions on where to start? Any information and resources would be 
useful. I'm already fairly proficient on rebuilding software and 
creating (s)RPMs, where do I go from here?

Cheers,

--Jon Atkinson