In The Eye Of Eternity raid, where you fight Malygos, on phase 1 he uses cyclone, where everyone gets in the air, and he starts hiting for a lot, like 2k dmg. As a rogue/warlock you can avoid this damage.
If you're subtlety rogue, as soon as he gets you in the air, use Shadowstep. It will get you back to him, and than you will fall to the ground, without taking any damage.
p.s I can't post screenshots cause my PC is kinda ****ed and the quallity is shit, but you have my contrib word that this works as of 12/28/2008 ^_^
Edit: If you want to know how to evade it with other classes check these threads.
Warlocks: http://www.mmowned.com/forums/wow-ex...x-malygos.html
Druids: http://www.mmowned.com/forums/wow-ex...dmg-druid.html
Combat Rogues: http://www.mmowned.com/forums/wow-ex...x-malygos.html