var imagenumber = 38 ;                          
var randomnumber = Math.random() ;
var rand1 = Math.round( (imagenumber-1) * randomnumber) + 1 ;
document.write('<img src="http://www.andreas-wopperer.de/heads/' + rand1 + '.gif" alt="[ @ndre@s wopperer ]" title="[ @ndre@s wopperer ]" border="0">')