Here are the defaults:

F1 Open help document.
Ctrl+A Select all
Ctrl+C Copy to clipboard
Ctrl+N New
Ctrl+O Open
Ctrl+S Save
Ctrl+V Paste from clipboard
Ctrl+X Cut to clipboard
Ctrl+Y Redo
Ctrl+Z Undo
Delete Delete

Also you can use Enter for "Done", and Escape for Cancel.

Keyboard shortcuts are defined in the moi.ini file, you can edit that file if you wish to create your own custom ones. See this message thread for more information: http://moi3d.com/forum/index.php?webtag=MOI&msg=35.1 Grendel has posted some .tif files there that gives a chart of the different command names that you can use inside the moi.ini file.

- Michael