All my games are unsigned Java Applets. You have to have to Java Runtime Environment (JRE) installed on your pc to play.
You probably have this installed already. If not, http://java.com/en/download/ is your friend.
"The security model behind Java applets has been designed with the goal of protecting the user from malicious applets...Applets can't access the local file system on the client computer, or make network connections to anywhere but it's own location."
Notwithstanding these restrictions, you'll probably have to approve the execution of this applet and/or you're going to get a Java warning which will make you decide whether you trust me enough to run this applet.
Even if it was my intention to harm your computer (it's NOT!), running a malicious program through my personal website would be kind of stupid, now, wouldn't it?
All of the above just to clarify that in case the applet doesn't run on your computer, it's probably due to the absence of the JRE or it has something to do with the security settings in your browser of choice.
If you get an 'incompatible JRE' error, download the latest version (link: see above) or go to your configuration screen, search for 'Java', and on the resulting sceen; lower security on the 'Security' tab to 'medium', reload the applet, then restore the security level to the previous level (high or very high).
My sincere apologies for putting you through all this.