1. right-click the YT title, select "Copy link target" from menu 2. in a terminal, type: youtube-dl -o "%(stitle)s.%(ext)s" 3. after that, paste the URL into the terminal, ReturnHowever, I wanted it even easier. The following little script brings up a text window, and checks the clipboard every second. If its contents look like a YouTube URL, it does steps 2. and 3., and logs the video title in its window. The output of youtube-dl is logged in the terminal (on my Lubuntu system at least), so you can see the details.
#!/usr/bin/env tclsh package require Tk 8.5 proc main argv { global g array set g {urls {} text .t} pack [text $g(text) -wrap word] -fill both -expand 1 $g(text) insert end "Youtube downloads from clipboard:\n\n" every 1000 check_clipboard } proc every {ms body} {eval $body; after $ms [info level 0]} proc check_clipboard {} { global g if [catch {selection get} cb] return if [regexp youtube.com/watch $cb] { if {$cb ne "" && $cb ni $g(urls)} { set title [exec youtube-dl -e -o %(title)s.%(ext)s $cb] $g(text) insert end $title\n $g(text) see end exec youtube-dl -o %(title)s.%(ext)s $cb & lappend g(urls) $cb } } } main $argvUpdate: in the version that came with Ubuntu 13.10, youtube-dl changed the variable %(stitle)s to %(title)s. Works now on my machine, for yourself, test which variant is better...
AMG: See also: http://www.jwz.org/hacks/#youtubedown (written in Perl)