LauncherPro Plus has been updated to include a new sms widget to go along with bookmarks, contacts and calendar which are already included. It seems to me that the aim here is to model what HTC has done with their scrollable widgets. For those who have never tried LauncherPro, go try it now! Due to market restrictions, you need to visit the LauncherPro site to get this great app. Here is a description from the Launcher Pro site.
New Messaging widget!. The fourth widget in the LauncherPro Plus series brings your SMS messages right to your homescreens. There are two styles to choose from, a card view that shows one message at a time, and a list view that shows all your messages in a list. Since widgets are now resizable, there's only one pre-set size for each style, you can resize them to your liking. After you're done resizing a widget, press the "Back" button on your phone to save the changes and go back to the launcher (just repeating this because I saw a lot of people complaining about their phone being "frozen" after resizing a widget).