w00t. I have successfully hacked NSStatusItem to look, if not act, like an NSMenuExtra.
drwxr-xr-x - English.lproj
-rwxr-xr-x 721 HotKeyCenter.h
-rwxr-xr-x 7782 HotKeyCenter.m
-rwxr-xr-x 141 KeyBroadcaster.h
-rwxr-xr-x 1543 KeyBroadcaster.m
-rwxr-xr-x 812 KeyCombo.h
-rwxr-xr-x 4179 KeyCombo.m
-rwxr-xr-x 348 MTApplication.h
-rwxr-xr-x 202 MTApplication.m
-rwxr-xr-x 15664 MenuInverted.tiff
-rwxr-xr-x 15644 MenuNormal.tiff
-rwxr-xr-x 1337 MenuTunes.h
-rwxr-xr-x 27446 MenuTunes.m
-rwxr-xr-x 456 MenuTunesView.h
-rwxr-xr-x 1179 MenuTunesView.m
-rwxr-xr-x 1844 PreferencesController.h
-rwxr-xr-x 20186 PreferencesController.m
-rwxr-xr-x 313 StatusWindow.h
-rwxr-xr-x 568 StatusWindow.m
-rwxr-xr-x 581 StatusWindowController.h
-rwxr-xr-x 1139 StatusWindowController.m
-rwxr-xr-x 257 main.m
-rwxr-xr-x 1500 submenu.tiff