Simple Reminder (SR) is an OPEN SOURCE .Net desktop reminder

Features:

Scheduler: Secondly, Minutely, Hourly, Daily, Monthly, Yearly, Once, Startup Reminder: Microsoft Agent, Email, External Application

Installation:
1. Install .Net Framework 2.0 or upper
2. Extract to any directory
3. If you don't have Microsoft Agent installed, get it from Microsoft Agent 
(Normally it's installed by default. You can check your system root,
e.g. C:\Windows\MSAgent, if there are some exe/dll files there, you got it)
4. You can get characters from Microsoft Office, or Microsoft Agent Ring

Usage:
1. Add and configure some events ...
2. Minimize to tray ...
3. Wait for your events ...

 

You can find latest SR release and source code at Google Code.