I couldn't help but smile when I read Simon Cozens' blog entry Missionary contact management with OS X He's a christian missionary and he recently noticed that his work is nothing other than Customer Relationship Management. Being also a known Perl hacker (and obviously a geek, too), he started combining tools to build his own contact and prayer management.
The first step was adding the fields "last contacted" and "last prayed for" to his address book. With some programming (using mainly the Mac::Glue Perl module), his calendar schedules a new contact with or prayer for a certain person when the duration since the last one reached a certain length. After an email actually is sent out, a Skype contact had been established or when Simon confirms having prayed for a person, the respective address book fields get updated. If his misses a due prayer, it gets scheduled again the next day.
This may seem geeky, but it's efficient. It's "Getting Things Done" in missionary work, leaving Simon the time necessary to do his important tasks: communicating and praying. It's exactly like I would like it to work.