LanguageTool - Free proofreading tool for OpenOffice, LibreOffice, Firefox, and Chrome.
OpenSubtitles.org - OpenSubtitles.org was developed for easy downloading and uploading subtitles for movies.
Grammarly - Clear, effective, mistake-free writing everywhere you type.
SubDownloader - SubDownloader - Fast and Easy Subtitle Downloader
Editsaurus - Highlights potential pitfalls in your writing to encourage good habits.
SubiT - With SubiT, you can download subtitles to your favorite movies and serieses, with a simple click.