automated magento commerce install on the fly

I need a solution where my web page users will be able to fill a simple (php) form (email, password, username = subdomain), and then Magento Commerce will be installed on the fly and its access data will be send to user. The point of this is, i will offer magento customization, and i want my visitors to have a "test drive" with magento commerce on a personal installation. Every installation will include preset orders, clients, Products, themplate.... I prefer magento commerce to installed on subdomain, like [login to view URL]