Is there a way to play a YouTube video at half the speed (like what we can do in VLC media player?)
I'm looking for a free solution if possible.
YouTube's video player has no native feature to change playback speed. However, there is a shareware app which lets you change the speed of videos played on online players: MySpeed!
Online video is everywhere – lectures, labs, tutorials, certification courses, seminars, news, sports and, of course, YouTube! MySpeed from Enounce lets you change the playback speed of Flash video without any loss of audio quality. (No chipmunk sound.) It’s like speed-reading for video! If your Windows PC or Mac can view videos on YouTube, MySpeed will work!
You can speed
down at half speed or speed
up YouTube videos. Here's how: Speed up YouTube Playback?
AnyVideoConverter will do a direct download from YouTube for you and convert to the format of your choice. It's free and good. Obviously not a solution within the browser but I didn't read that was a requirement for you.