An application settings manager that allows you to quickly categorize and manage all those miscellaneous application settings that are clogging up your web.config file. As a bonus, you can let your end users manage their own settings with the supplied editor.

A pair of server controls, DialogOpener and DialogCloser, that you can drop on a web form to enable you to open a dialog, and when the dialog is closed, cause a server event of your choice to fire on the main form.

Creating child controls, rendering, wiring up events, and managing viewstate when building an advanced custom server control that embeds other server controls (composite control).

It's not about feature support. It's about culture.