I've just finished working on a WPF, a pretty standard inventory system for widgets & gadgets. A hierachurial structure to the data that lends its self to a tree-view structure - essentially each node has a parent-child relationship, where a node can have multiple child nodes and each node has a reference to it's parent. The app is a simple a CRUD application with some UI tweeks on how the data was to be displayed - visualising the modified nodes in the tree and hows these affected the parent node. What made this interesting was the fact this wasn't a new app from the ground-up, it was literally only a new UI, the database was already established in a production environment and had been for over 5 years, what made this interesting was the client was providing the DAL & BLL for the application - we were abstracted away from the database. All queries for data are returned via strongly typed data tables and all commands (updates) are done via explicit methods on th...