Let us know what tools you use for your designs, and how you would rate them.

I have used DbDesigner4 http://fabforce.net/dbdesigner4/

and MySQL workbench (which is still in beta) http://forums.mysql.com/list.php?113

Dbdesigner4 is good but is no longer maintained, and is being replaced by MySQL workbench.

MySQL workbench is still in beta and still needs a fair bit of polish, but it looks promising.

Here are some other ER tools that I am aware of of:

- dbwrench (http://www.dbwrench.com/) Cross platform (JAVA)

- Microolap (http://microolap.com/) For windows only.

- SQL Manager (http://www.sqlmanager.net)

If you know of others, or would like to be listed, please make a post below.

Take a look at [a href="http://www.xcase.com/"]Xcase[/a], a nice ER, [a href="http://www.xcase.com/"]Database Design Software[/a].
It has a nice user interface and tight support for various DBMS

I am using CaseStudio

I use H-SPHERE