Personally I can only go on what Ive played or seen played, because I tend to like the look of everything till I see its holes exploited.
Epic Game I played had several interesting combos: Barbarian/Sorceror/Frenzied Berserker(Epic)/Rage Mage
Wizard/Cleric/True Necro (Epic)/Mystic Theurge
Standard Games
Master of Many Forms
Ghost Faced Killer
Daggerspell Shaper
Foe Hunter(was 3.0 not 3.5)
Slayer of Domiel
Black Flame Zealot
Bladesinger
Order of the Bow Initiate(especially powered up with Ready Shot from Heroes of Battle)
thats a few. If I think of more Ill post them