/rot13
.s/rot13/click the text to rot13/
a
<span onclick="
function rot13(txt) {
    var buf = '';
    var intag = 0, inent = 0;
    for (j = 0; j < txt.length; j++) {
        var c = txt.charCodeAt(j);
	if (intag) {
	    if (c == 62) intag = 0;
	    buf += String.fromCharCode(c);
	} else if (c == 60) {
	    intag = 1;
	    buf += '<';
	} else if (inent) {
	    if (c == 59) inent = 0;
	    buf += String.fromCharCode(c);
	} else if (c == 38) {
	    inent = 1;
	    buf += '&';
	} else if ((c >= 65 && c <= 90) || (c >= 97 && c <= 122)) {
	    buf += String.fromCharCode((c<=90?90:122)>=(c+13)?c+13:c-13);
        } else {
            buf += String.fromCharCode(c);
	}
    }
    return buf;
}
this.innerHTML=rot13(this.innerHTML);">
.
$
a
</span>
.
wq