Sometimes simple is better, and Osmo is a good example of that: a simple, lightweight personal information manager that lets you handle all important tasks and events in an easier way.
Osmo has a somewhat primitive interface, with tabs for each one of its tools: calendar, tasks, contacts, notes and an options menu to configure the program's behavior and appearance. In a way looks like a Windows 98 app, rather than a program developed in 2009.
But maybe this simple design is what makes Osmo a really handy personal manager. It has one of the most fully featured calendars I've seen in this kind of tool, including information about days and weeks that have gone by, a date calculator, a full-year calendar and even a special version for printing.
The Task utility in Osmo is also quite useful. It enables you to sort tasks according to priorities and set alarms for them, with support for recurrent warnings. As for Contacts, each entry displays an array of fields to fill in, including birthday, personal photo and custom tags.
Osmo is a surprisingly complete personal information manager with an old-fashioned interface design.