This DOS script can be used with YAM.
If in a mail an URL is given , a double click will either open the URL in muiOWB or if it points to a YouTube video, will play it.
I installed it in sys:utilities getvideo drawer. You may have to edit for your system.
.KEY url/A
;called from YAM "on clicking URL" sys:Utilities/getVideo/PlayYTube %p
set metube `cut "<url>" char -28`
cd sys:Utilities/getVideo
IF $metube EQ "http://www.youtube.com/watch"
; Requestchoice video "<url>" ok
Getvideo.rexx "<url>" play
ELSE
cd datas:muiowb ; datas:muiowb/owblauncher does nothing
waitforport OWB.1 timeout 0; returns 0 if found ; 5 if not
IF WARN
RUN owblauncher
waitforport OWB.1 timeout 10
IF WARN
echo "waited not long enough or OWBlauncher problem"
ELSE
wait 3 ; the rexx command below will not work without it
RX "address OWB.1 'OPEN NAME ""<url>"" '"
ENDIF
ELSE
RX "address OWB.1 'OPEN NAME ""<url>"" '"
ENDIF
ENDIF
cd sys:Utilities/getVideo
If you solved this in other way would be interested in knowing how