[R] How to program with colleagues

[Alaios]

Dear all,
my colleagues and I have to write some R code for some of our projects.
I would like to ask you help to organize us a little.

a. Do you know if there is any system that can convert our R scripts to html pages with some nice dependency graphs (which functions calls which).

b. Could you please suggest me an easy way to exchange the R code with my colleagues. I know about these version systems but unfortunately they look pretty bizarre to me.

I would like to thank you in advance for your help

Best Regards
Alex