I've been asked for this extension for a while. Its idea is similar to 2 popular extensions: Include Exclude and Show Hide but expand the ability with lots of options! Now you can show or hide not only meta boxes, but custom fields and any DOM elements by other fields' values!
We can say that this extension is an update version of Show Hide extension, but with more options and features. It works with fields and more interesting - with other DOM elements.
The strength of this extension includes also the number of conditions. In the Show Hide extension, you have only one choice for checking the value equally. But here you can check for equal, between, in, start_with, end_with, contains or use regular expression. You can also use not operator to make negate operator.
For more details, please check out the extension here. We hope it's a good addition for your needs!