LF: PHP Blog Creation Script for Multiple Users Where Users Get Their Own Blog On My Domain


I am looking for a script where I would host a domain (http://mydomain . com) and when users would sign up they would then be able to select from a few “themes” and create their own blog (http://mydomain . com/theirName)

BONUS would be for each user to be able to add Google ads to their blog and have their own admin section.
BONUS 2 - A way for me (the site owner) to be able to charge for the bloggers to host their site or pay for certain features (more than one theme, use their own theme, etc …)

If such a script exists then please point me to it, if not I would hope someone would consider building one.

Thank you