MyPassMan stores your passwords in an encrypted plain-text file.
There are many others like it, but this one is mine.
MyPassMan is written in Java and requires a Java runtime version 6.0 or newer to run.
You can download Java from Sun Microsystems here.
If you are not a programmer, then you should probably download the Java Runtime Environment (JRE) 6, otherwise download JDK 6.
Once you have a Java runtime installed on a Windows system, you should be able to simply double-click the mpm.jar file to run the program.
If that doesn't work, or on a UNIX system, you need to ensure that the Java runtime is in your PATH by typing
java -version
at a command prompt. If Java spits back a version string, then you can type
java -jar mpm-x.xx.jar
to get it running (where mpm-x.xx.jar is the name of the jar file you downloaded from
SourceForge).