I recently had an odd request, they wanted their site to appear as HTML but run PHP; my first thought was why? but, if thats what they want, thats what they get.
It turned out to be a very simple task. If you open up your .htaccess file and add the following line:
AddType application/x-httpd-php .html
.html will execute as PHP!
Job done. 
I had a problem recently – I needed to randomize an array – of course I could have used the PHP function array_rand however, this overwrote the existing keys with numbers – not good! as I need to use those keys as part of my display – okay, not best practice but i’d set it up this way thus far, why should I change it? Therefore I discovered a function that allowed me to do exactly what I needed, it randomizes the array whilst keeping the existing keys !
function array_rand_keys($array, $limit = 1) {
$count = @count($array)-1;
if ($limit == 0 || !is_array($array) || $limit > $count) return array();
if ($count == 1) return $array;
for ($x = 0; $x < $limit; $x++) {
$rand = rand(0, $count);
while (isset($rands[$rand])) $rand = rand(0, $count);
$rands[$rand] = $rand;
}
$return = array();
$curr = current($rands);
while (count($return) != $limit) {
$cur = 0;
foreach ($array as $key => $val) {
if ($cur == $curr) {
$return[$key] = $val;
$curr = next($rands);
continue 2;
} else {
$cur++;
}
}
}
return $return;
}
