Great Downloader easy to use can convert into multiple file formats. Fast and impressive
Video DownloadHelper - Browser extension to download videos from the Web
TinyJPG - Compress JPEG images with perfect quality and file size
youtube-dl-gui - A cross platform front-end GUI of the popular youtube-dl written in wxPython.
Promo Instant Image Resizer - Automatically optimize images for web & social media (free!)
Youtube Video and Audio Downloader - Download YouTube videos in all available formats and extract the original audio files.
Compressor - Compressor adds power and flexibility to Final Cut Pro X export.