There are two useful YouTube addons for wrangling YouTube, without needing the services of some third-party online outfit in Whereizitagin.

Youtube Playlist Total Duration is a UserScript that shows the total duration of the playlist. Useful for those who need to know how long a software-training or hardware-setup playlist will take to view. Tested and working, but note that you must re-load the page to see the correct time for the playlist.

Got a slow presenter, and need your learning playlist running a little faster? The Chrome browser addon Any Youtube Playback Speed does the job nicely, and with fine increments on a simple slider. Again, tested and working.

Small changes re: time and speed, but both are very useful.