Generating .aspx pages on the fly over the server.

Hi, my question is, how can i dynamically create a .aspx page and saves it on server say for each user that has been registered.. it's more like Profiles for each different user.. how can i achieve this, i want to make is simple, not very complex.. like the web page link would be like this.. http://www.MyURL.com/Profile/NewlyCreatedPage.aspx .. where the .aspx is the newly created page nd stored in Profile Folder over ther server.. can i assign a master page to it for static look?

Thank U
...