CadEditor is the level editor for many classic console games, such as Chip & Dale, Darkwing Duck, Duck Tales 1-2, Little Mermaid, Tiny Toon Adventures, Jungle Book, Flintstones, Little Nemo, Megaman 4-6, Contra Hard Corps.
Now there are 1172 configs for levels from 118 different games (and the list grows with each update).
It also used as the level viewer to find secrets and easter eggs in this games.
CadEditor using the system of plug-ins allowing users to add new games by themselves. It also supports user scripts to automatize work with CadEditor.
In bundle with CadEditor comes plugin for exporting map and TSA allowing to export those in both binary and image forms for use in homebrew projects.

via http://www.romhacking.net/forum/index.php?topic=26201