Lists:
Database Answers
Commercial:
AllFusion ERwin Data Modeler
ER/Studio
DeZign
Case Studio
DDS-Lite
Data Architect
Open Source/Free:
Abeille – DB2, DaffodilDb, HSQLDB, JDataStore, McKOI, MySQL, Oracle, PointBase, PostgreSQL or Sybase
Clay – Eclipse plugin
DBDesigner – MySQL only