CONV. - Convert YouTube video to MP3, GIF or MP4
Giphy - Search all the gifs and make your own animated gif
Downie - Video download for OS X. Downie supports at this moment over 1,000 different sites.
GIFmaker - GIFmaker gives you the freedom and flexibility to create unique, professional GIFS that are on-brand, on your own!
Yout - YouTube to Mp3 Converter
GIPHY Says - Turn your words into animated GIFs!