customized private wiki (Score 1)

What works for me: a stock wiki + a custom 'daily reminders' script. When I need to be reminded of something, I put a note on the wiki's 'ReminderList' page, along with the date I need to be reminded. The daily reminders script is a cron job that moves 'today's' reminders to the wiki's home page. When I log in, the day's reminders are waiting for me. (The script allows recurring reminders, too). My mother appreciates that I no longer forget her birthday or anniversary.

Adding that to the ease of maintaining to-do lists in a wiki, for me it's a hands-down winner.

Wikis are customization-friendly, too. I wrote a script which checks the wiki's 'Project<foo>' pages and generates a summary page listing the status of all projects. So I always know where I'm at, even when buried under six projects.