Is there any good tool for making Database Design and Prototypes? I would like to have a good tool for designing the Database Schema with all the tables, columns, data types and relations. Today I mostly do this with pen and paper but I would like to do it in a good design tool. 

Is there any good (and maybe free) Database Design tool?
I started using NORMA (link fixed Oct 2011) which is useful to capture the relationships and constraints in plain English. See Object Role Modelling too.

This will generate XSDs and SQL scripts.

I hope never to see an ERD ever again...