I've released version 1 of a java-based ship combat simulator. You can download it at:www.geocities.com/saber_marionette_cherry/index.html
(click on the "click here" button)
Currently it only supports ships, not fleets; I may add fleets tomorrow. Starbases would be nice too. Also, an applet with text boxes would be nice. It runs from command line now; the instructions are very simple (and on the website).
To install, just unzip it into a directory. To get a command line you can type Start->Run->"cmd"
If you don't have java, go tojava.sun.com/j2se/1.5.0/download.jsp
Click on:Download JRE 5.0 Update 6
...or if you are a programmer,Download JDK 5.0 Update 6
Then click on:Windows Offline Installation, Multi-language
...then install it.