Incomplete file downloaded with FlashGet, a download manager; created when a download begins and serves as a placeholder for the completed file; when the download finished, the file is saved with the original extension.

If a JC! file download is paused or stopped, it can be resumed by FlashGet as long as the same file is found on an available server. Files that have been partially downloaded with FlashGet may also use a .JC extension (without the exclamation point).