You can store the result of a function call to an array ... yes.
You could even store the name of the function you want to run, and call it from the array. E.g.:
<?php
$array = array
(
'somethingToRun' => 'date'
);
echo $array['somethingToRun']('m/d/Y');
THat would run the [man]date[/man] function.