just been having a flick through youtube for anything on the mournes, most videos are pure tripe from a shaky phone and loads of wind noise but here's a few good ones you might be interested in, feel free to add more you find, my internet connection is pretty slow so takes me ages to find the good ones :'(
a few lads from kildare go camping in annalong wood
http://www.youtube.com/watch?v=E1vMrHWi2aQ
the electric bray / gravity hill / magnetic road
http://www.youtube.com/watch?v=RVwuLifoK40
a 10year old does the seven sevens
http://www.youtube.com/watch?v=UVR2TZEzdn4
the dirtier your boots, the clearer your mind - some nice camera work here
http://www.youtube.com/watch?v=qv5pK_iiAAk&feature=related
mourne mountain national park proposal
http://www.youtube.com/watch?v=BhbcOz3mTNI
dave macleod climbing divided years (buzzard's roost, slieve binnion)
http://www.youtube.com/watch?v=OCPASN3yzsI
ice climbing on eagle mountain
http://www.youtube.com/watch?v=_s9FOsBzlj4
one of the better shaky cam vids ;D (Lenny & I on Tievedocksumfin)
http://www.youtube.com/watch?v=dePz27GwvGY
Mountain Biking in Kilbroney Forest Park
http://www.youtube.com/watch?v=vEPHasff0hM&feature=related
Mountain Biking Down Commedagh !!
http://www.youtube.com/watch?v=9Dqh1yR48Jw&NR=1&feature=fvwp