To another machine: in IE use File>Import and Export to export your favorites. That makes a nice file bookmarks.htm that you can import again in IE on another machine.

Firefox has an option to directly import IE favorites, although I don't know if it's only offered when installing it or accessible at any time. But the bookmark.htm format IE makes when exporting is understood by the import option of the Firefox bookmark manager also, so that's a good way to do it in any case.