The DCE backend module
Under Admin Tools in the main navigation of TYPO3 backend you find "DCE" which leads to this dashboard:

Dashboard
On the dashboard, you see all DCEs you have created.
Hint
DCEs are TCA records stored on pid=0 (root level)
You see pieces of information for each DCE:
- Status (enabled/disabled)
- Identifier
uid
-
Usage (amount of content elements using this DCE) - click on it, to see more details
- Infos about features used, like DCE container, TCA mappings
- Amount of fields used in this DCE
Also when you have mapped values to TCA columns of tt_content, you get an Update TCA Mappings button, which updates the values of mapped columns, by given FlexForm values.
More stuff
In the backend module, you also find helpful links to Documentation, Facebook page, etc.
Also, you can clear the system caches, switch to list view and create and edit DCEs.
You can donate and see other donators in the hall of fame.