Connected Field is a useful component for SharePoint. You can now create cascading master-detail relationships between two or more lookup fields in SharePoint lists and document libraries. Filter your city column values by the selected country, it is as easy as it should be.
1. Support for site columns and content types - now you can create the master-detail relationship at the root site and reuse it throughout your site collection.
2. Support for multi-choice lookup fields - both master and detail fields can be set to support multiple values. When several master values are selected, the combined list of detail values is available for selection.
3. Unlimited number of cascading levels - you can chain together as many columns are you like, each parent can have unlimited children and each child can have its own children. Note: you may experience some performance degradation when too many columns are added. Up to 12 columns may be created on a slow system without a significant performance penalty.
4. Looks and behaves similarly to the built-in lookup column, no user training required - end users will not notice any change in the behavior or appearance.
5. Enter new values directly from the column
6. Operates both as a cascading lookup and as a regular lookup
7. Supports filtering returned values according to a pre-selected SharePoint view
8. Add addtional columns from the source list and update their values automatically
9. Based on ASP.NET 2.0 AJAX capabilities.

Connected Field will help you extend Microsofts SharePoint functionality by customizing the the lookup fields.

Connected Field Features:
1. Run the installation file to extract and install the product. You must be a farm administrator to accomplish this task.
2. Create a new list called Product Categories, and fill it with sample data.
3. Create a second list called Products, and add a regular lookup field to Product Categories, name it Category and fill this list with sample data.
4. Create a third list called Sales
5. Add a lookup field to Product Categories, name it Category
6. Add a Master-detail lookup field and define it according to the following
* In the lookup section define the field as a lookup to Products.
* In the Parent Field select the Category field you (the lookup to Product Categories).
* In Link Column choose the Category(the field that was mapped to Product Category in Products - the filtering field in the lookup list).
7. Now add a new item to the list and see that as you choose a value from Category field, the Products field will be filtered accordingly (no page refresh is needed

Requirements:
* SharePoint

The license of this software is Free Trial Software, the price is $449.00, you can free download and get a free trial.