<?
$tomorrow = mktime (0,0,0,date("m"),date("d")+1,date("Y"));
print "tomorrow: ". date("m.d.y", $tomorrow) . "<BR>\n";
$yesterday = mktime (0,0,0,date("m"),date("d")-1,date("Y"));
print "yesterday: ". date("m.d.y", $yesterday) . "<BR>\n";
$specificday = mktime (0,0,0,12,1-1,2002);
print "secificday: ". date("m.d.y", $specificday) . "<BR>\n";
http://www.php3.de/manual/en/function.date.php
http://www.php3.de/manual/en/function.mktime.php