Create your own Bank System Version 2
This is a simple Bank script for a Simple User system that has a money system. Have a look, learn some, get smarter 
CODE
<?php
/*
Simple Bank Script by Demonic
*/
##########
##Special Notes:
##edit the `cash` column name to fit your needs and the users table to fit your needs of your table name
#########
########SQL##################
#ALTER TABLE users ADD bank INT(255) DEFAULT 0;
#
#if your users table isn't called table change it same goes for your points system
########Connect to your database##########
include ("database.php");
#########End Database include############
###Set up some varibles###
$username = $logged[username];//this is the cookie of the loggedin username.
$update_bank = $_POST['bank'];//submit button.
$selection = $_POST['addtobank'];
###end the varible checks etc..##
if($username){
//if the update bank button was pressed update bank total
if($update_bank){
//selects the total bank,cash ammount from database.
$bank_total = mysql_query("SELECT `cash`,`bank` FROM users WHERE username='".$username."' ") or die(mysql_error());
//gets the array of money from the users table of cash,bank total
$totalb = mysql_fetch_array($bank_total);
//check to see if the ammount of cash you set is more then you have
if($selection > $totalb[cash]){
die("You don't have that much money to put in bank");//show the error name
}
$totalcash = $totalb[cash]-$selection;//subtracts the total of cash
$totalbank = $totalb[bank]+$selection;//adds to the total in the bank
//update the cash and bank total
$update_the_totals = mysql_query("UPDATE `users` SET `bank` = '$totalbank', `cash` = '$totalcash' WHERE username='$username' ") or die(mysql_error());
//tell us we're done.
echo ("Your Bank and cash were updated. Cash Before: ".$totalb[cash]." Cash After: ".$totalcash.",Bank Before: ".$totalb[bank]." Bank After ".$totalbank."");
//elseif the button wasn't submited
}else{
//select data from the DB to show current money.
$total_all_together = mysql_query("SELECT `cash`,`bank` FROM users WHERE username='".$username."' ") or die(mysql_error());
$total_currently = mysql_fetch_array($total_all_together);
echo ("
<h1>Total cash:".$total_currently[cash]." Total Bank: ".$total_currently[bank]."</h1>
<form method='post'>
<input type='text' name='addtobank' /><input type='submit' name='bank' value='Update Bank' />
</form>
");
}//end else
}//end if
else{//else tell them to login.
echo ("please login to add money to the bank");
}//end else
?>
Sunday May 27, 2007 | http://www.totaldream.org/article/31-create_your_own_bank_system_version_2.html