It's not especially easy or especially pretty, but my sony ericsson has released an unofficial web app for creating your own Xperia X1 panels. The basic idea is pretty simple -- code up your own HTML files and a few thumbnail screenshots (for the panel browser), upload the files, and then download the panel they conveniently create from all that.

Sure, they're not going to be as powerful as C++ panels, but hey, you don't have to learn C++ to create them. You can even create links in your html file to applications and folders on the Xperia, so you can roll your own quick-start panel as a nice start if you like. Be aware that there are some pretty tight constrictions on what you can do (hint: it has to be supported by Pocket IE 5).

While you're setting up your custom HTML-based panel, we'll be over here wondering if alternate today screen platforms/standards are good for Windows Mobile as a whole. Panels, TouchFlo 3D, TouchWiz... they're all very pretty, but they're all also very proprietary. Do you care? Should you?