These are 10 man only.
Lord Marrowgar:
[youtube=425,350]http://www.youtube.com/watch?v=zFTceGrZIVk[/youtube]
Lady Deathwhisper:
[youtube=425,350]http://www.youtube.com/watch?v=JXTE2VJSJS0[/youtube]
Gunship Battle:
[youtube=425,350]http://www.youtube.com/watch?v=WBAnLhFk2EE[/youtube]
Deathbringer Saurfang:
[youtube=425,350]http://www.youtube.com/watch?v=eBkgaYlKA5o[/youtube]
Rotface:
[youtube=425,350]http://www.youtube.com/watch?v=v0St5xnlifM[/youtube]
Festergut:
[youtube=425,350]http://www.youtube.com/watch?v=L_0n38eMJXU[/youtube]
Professor Putricide:
[youtube=425,350]http://www.youtube.com/watch?v=35p21sdb4us[/youtube]
Blood Princes:
[youtube=425,350]http://www.youtube.com/watch?v=0SBoGZEf3Dk[/youtube]
Blood Queen Lanathel:
[youtube=425,350]http://www.youtube.com/watch?v=ZdRvXHzSDD0[/youtube]
Valithria Dreamwalker:
[youtube=425,350]http://www.youtube.com/watch?v=R10LIcRiFH8[/youtube]
Sindragosa:
[youtube=425,350]http://www.youtube.com/watch?v=o89tT2o87r0[/youtube]
Fleecy got the Wiki updated some also:
http://wiki.twilightonalex.com/Icecrown_Citadel
Added Dreamwalker and Sindragosa videos for 10 man. Not going to post video for a Lich King to avoid ruining fight for others.
I dug this up which is a rather nice summary of healing Valithria. It's from the perspective of a Resto druid, but for all of our portal jockeys it should help a lot.
http://fallingleavesandwings.wordpress.com/2010/02/04/healing-valithria-as-a-resto-druid/
Seriously a 54K heal, thats just crazy