Here is a clock I wrote which updates and will alert you with the time every fifteen minutes. Unlike some other clocks it shows "12" at midnight instead of "0" and it still shows correct am and pm. I tried it on Netscape 4.5 and a beta version of MSIE5.. it worked fine. I have explaination of the expressions I used in the script to help you change it to suit your needs. If you use it please give me a link to my WorkStation. You don't have to but I like people to see my pages too...
Here are three different ways you can make your clock look. MSIE won't show the enlarged font but netscape will. Niether will show the different bgcolors.
See it in operation at My WorkStation for WebTV