As some of you already know, Microsoft shipped a control called the WebPartPageMenu in Beta1 that allowed you to select the design mode of WebParts on a web part enabled page (eg. Edit mode, Design Mode, Catalog mode etc.). This control has been dropped for Beta2 and although it was a limited control, I still found it quite useful, especially when experimenting with WeParts.
With this in mind, I have created the WebPartPageModeSelector server control that has been created using the Beta2 product (well as close as for now) and does essentially the same thing as the recently demised WePartPageMenu. It displays either a dropdown list or a list of radio buttons, depending on what zones/features you have on your page, and sets the display mode by setting properties of the webPartManager control that is present on the page. It also supports AutoPostBack (in which case no "Apply" button is displayed), allowes easy changing of the display style from DropList to RadioButtons, altering of the "Apply" button text and a couple of other things.
Its free, comes with full source code, and works fine on the latest Beta2 builds. Thought some others might find it handy too.
If you are after any specific features, I'd be happy to put them in, just send the suggestions my way.
Note: There is other stuff on the download page here for the curious.