[Orgmode] About diary and time tracking

[Rustom Mody]

I gather (dont recall exactly from where) that there are alternatives
to using the builtin emacs diary (Subsection: Calendar Diary
Integration in Section Agenda views).

Likewise I think Carsten has written somewhere that the time tracking
setup of Sacha Chua at
http://sachachua.com/wp/2007/12/30/clocking-time-with-emacs-org/
has largely been incorporated into later versions of org.

So my 2 questions...
 - What are the diary alternatives (if any)?
 - What is the minimum setup to get some of (not necessarily all the
bells and whistles) Sacha's time tracking stuff?

Context: I may be demoing org to a corporate and ease of setup is
often a bigger selling point than a zillion sophisticated
possibilities