You-Get - Command-line utility to download media contents from the web
GIFMaker for Mac - GIFMaker – Created a GIF from a video or Images is the easiest way to create an animated GIF on your Mac.
Softorino YouTube Converter - Download YouTube video & audio. Watch and listen offline
Giphy - Search all the gifs and make your own animated gif
CONV. - Convert YouTube video to MP3, GIF or MP4
GIPHY Says - Turn your words into animated GIFs!