Just getting that effect is relatively easy, particularly depending upon what exactly you mean by flashing. An ordinary HTML form has a flashing cursor of sorts in it's text fields:
Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<title></title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<style type="text/css">
label {
font-family: sans-serif;
font-weight: bold;
}
</style>
<script type="text/javascript">
onload = function(){document.forms[0][0].focus();};
</script>
</head>
<body>
<form action="page1.htm">
<div>
<label>Login > <input type="text" name="name"></label><br>
<label>Password > <input type="password" name="password"></label><br>
<input type="submit" value="Go!">
</div>
</form>
</body>
</html>
But then the real question arises:
How secure and flexible do you want this to be?
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