<meta http-equiv="refresh" content="15; URL=this.html">
What if your visitor doesn't want it to reload that often? (Think:
dial-up, or people using IE with more than one window open[1]). Plus,
some browsers have the option to disable meta refresh.
<script>
function reload() {
location = "this.html"
}
setTimeout("reload()", 1000);
</script>
Won't work for around 15% of your visitors.
To the OP: Much as you might not like it, Leif's solution is both the
best for your visitors and the most reliable.
[1] I hate the way IE brings the window to the front when a page
finishes loading.