Far too many people think of Lotus Notes as an "e-mail system that can also do some applications" when it really should be thought of as "a platform for diverse collaboration applications, one of which just happens to be e-mail."
Even some IBM people have a tendency, when a new Notes release is being described, to spend so much time highlighting improvements in the Notes Mail application that it wouldn't bee too difficult to get the impression (quite wrongly, of course) that Lotus Notes is all about e-mail.
Once upon a time -- in the 1990s -- Lotus used to distribute a bundle along with Notes a bundle of quite useful example applications; but alas not any more. I'd strongly recommend to IBM that they start doing this again!
However some of the "oldies but goldies" are available. If you're interested in seeing and getting them, go to either http://asiapac.com.au/Links/NotesDomino.htm or http://notestracker.com/Links/NotesDomino.htm
Then scroll down a litttle (not very far from the top of the page) to the QUICK LINKS ON THIS PAGE menu, and click on the link Some "trusty old Lotus Notes applications" to be sent to the download links.