instiki/app/views/wiki/new.rhtml

<% 
  @title = "Creating #{WikiWords.separate(CGI.unescape(@page_name))}"
  @content_width = 720
  @hide_navigation = true
%>

<%= render("#{@web.markup}_help") if @web %>

<form action="../save/<%= @page_name %>" method="post" onSubmit="cleanAuthorName();">
<p>
    <textarea name="content" style="width: 450px; height: 500px"></textarea>
</p>
<p>
    <input type="submit" value="Create" /> as 
    <input type="text" name="author" id="authorName" value="<%= @author %>" onClick="this.value == 'AnonymousCoward' ? this.value = '' : true" />
</p>
</form>

<script language="JavaScript1.2">
function cleanAuthorName() {
  if (document.getElementById('authorName').value == "") {
    document.getElementById('authorName').value = 'AnonymousCoward';
  }
}
</script>