You can see a detailed list of all the custom widgets you've created. They can even be sorted into categories.
To access the list of all your custom widgets:
Login to the Member Area
Along the top tabs click Website and then Website Content on the blue menu just below
Click Home Page Custom Widgets
You will see a series of filters along the top. These filters let you only see the custom widgets that appear on your website, specific Custom Pages, specific Bulletins, etc.
Once you go to the appropriate list of widgets, you Preview, Edit, or Delete any widget by clicking on the dropdown menu under the Actions column