Under Creator Studio, Video Manager, Playlists, New playlist, a new playlist can be created. However this requires logging in.
Can a YouTube playlist be created without logging in?
Get all the video IDs, then create a URL like so:
http://youtube.com/watch_videos?video_ids=AAAAAAAAAAA,BBBBBBBBBBB,CCCCCCCCCCC,DDDDDDDDDDD
It will redirect you to a link like this:
http://youtube.com/watch?v=AAAAAAAAAAA&list=EEEEEEEEEEEEEEEEEEEEEEEE
If you want to share, you can shorten it to this:
http://youtube.com/playlist?list=EEEEEEEEEEEEEEEEEEEEEEEE