I just concieved another unique build. It's a bit of a combination between a couple other combos I've liked to use.
First is the Cleric/Blackguard/Divine Champion. At first glance its a pretty ordinary Evil Divine hodgepodge, but there are two nice tricks. First is charisma is useful in many ways (Smite, Turning, Sacred Defense, and have a dozen more ways). Second is the feat "Extra Smiting". If you choose the destruction (i think) domain you get a single smite from each class. Extra Smiting gives you two extra smites for EACH of those, so you end up with 9 smites per day... Not bad.
Another combo I liked was something you can do with a pure bard. Bards can demolish alot of characters will saves. It starts with Curse Song and Inspire Jaring wich reduce all enemies will saves by 3 and 2 respectively (no save). Then hit your weakened opponents with a Mind Fog (-10 will saves). Suddenly everyone is helpless against Domination, Confusion, Charms, and Sleeps until voice wears out and you have to stop for a drink of water. I like to throw in some Enchantment Spell focus for good measure.
Then it dawned on me. Blackguard gives ANOTHER aura that reduces saves, and the bard works great as a charisma based character. So heres what I am thinking:
Bard(14)/Blackguard(3)/Divine Champion(3) - Lvl 20
Bard(14)/Cleric(1)/Blackguard(10)/Divine Champion(5) - Lvl 30
Bard(19)/Cleric(1)/Blackguard(10)/Divine Champion(10) - Lvl 40
I'm not sure how epic feats are going to play into this build (especially the bard part), so there is plenty of tweaking to do. I know smiting isn't a super pwerful ability, but its useful none the less. At the very least its a kind of poor mans true strike with a bit of damage too. Another thing to consider is while turn undead won't be very useful, there are feats that you can exchange turns for Charisma based bonuses. I don't think this is a super powerful build, but just a nice blend of classes that complement eachother nicely.