I'm still plugging away with DeZign for Databases 2.5.1 and still like it.
[ DeZign for Databases is an Entity Relationship Diagramming tool (ERD tool), and is used to create databases for database servers like MS SQL Server, MySQL Server, Oracle, Access, PostGreSQL, Informix, Sybase, etc. ]
I've been using DeZign for a few years now, and it really does most of what I need. The upgrade to v3.x is $120, and though I've given the trial a spin, I still don't use it everyday, and can't really justify the upgrade. That isn't to say DeZign 3 isn't sweet - it is much nicer than v2.
Compared to other tools like ErWin, it's lacking, but very few people need ErWin. I've used that before, but it's not really necessary. I still end up coding a lot of SQL manually, and the extras I'd get from a higher end package I can do myself once I've got my basics down, which DeZign is perfect for.
Some things take a bit to get used to with DeZign, but I've found the best thing to do is simply lay out all my tables then add primary keys ONLY where absolutely necessary. Once that's done, I add in all my relationships. Next, I weaken relationships in tertiary tables that I use for tracking many to many relationships to create primary foreign keys in them, which DeZign automatically adds in. Last on the list is putting in columns that will not be used for data integrity (i.e. They aren't part of the primary key and are not foreign keys).
Once it's done, I'll go through and recheck all my tables, columns, and relationships. Invariably, I change my mind on a few things and rework the data model a bit. Some things in DeZign are a bit clunky (you can't make multiple selections) and take a bit more time, but overall, it gets the job done efficiently.
DeZign is from a small company in the Netherlands called Datanamic, and you can find them at http://www.datanamic.com. If you end up buying it, please tell them that I deserve a free upgrade =)
Cheers,
Renegade