If you've ever tried to migrate an entire WordPress install across different domains or servers, whilst trying to keep things like widgets and plugins alive, you'll be aware of the difficulties. You can't do a search and replace on a database dump because it corrupts serialised PHP data in the database. The only quite unpalatable choice is to fix the serialisation strings by hand - slow, and error-prone.
We have one site that runs something like 150 widgets - a nightmare in a migration, and I really wanted to have a local, byte perfect copy of the site on my local machine for proper testing and experimentation.
I also knew it would be a pain and it finally motivated me to write a tool that allows you to do a search and replace across an entire database schema (or database depending on the way you like to talk about these things

).
It's not user friendly - in fact, it's built very much as a developer's tool right now, and I haven't yet been through and tidied up the code although I have tested it. I personally am very new to PHP although I'm an experienced developer, so I'm aware that because of this the style of the code is all over the place - so apologies for that.
Obviously it's supplied without guarantee - more info about this safe(r) database search and replace tool over at:
http://www.davesgonemental.com/mysql...erialized-php/