An 8th level egoist that I threw at the party gave them terrible trouble. For the big fight he buffed himself thusly:
Claws of the Bear
Polymorph self to Troll form (reach, bear claws got bigger, more str and armour)
Animal Affinity - boost Str
Animal Affinity - boost Con
Duo-dimensional hand (overall his claws did 2d8+8 with a crit on 17-20)
Schism (the schismed mind manifested Body Adjustment each round as necessary from a power crystal to keep him going).
With a ring of counterspelling(dispel magic) to help keep his buffs in place he was a holy terror who killed one of the PC's before making a run for it.
One of my current players is an 8th Savant, and in his support role he probably saved lives last night with his inertial barrier on the party tank. His powers are
4th Inertial Barrier
3rd Cone of Sound, Dimension Slide
2nd Concussion, Animal Affinity, Body Adjustment
1st Featherfall, heat metal and some others I don't remember at present.
He now has a 20 Con, which he normally boosts with Animal Affinity, and he triggers Concussion powers as his most common form of attack (DC15, typically +6 or +7 on the roll so he gets them free a little over half the time). His Dex is pretty good, and also gets boosted by animal affinity, to help with ranged attacks.
(nb we houseruled concussion to be a ranged attack (not ranged touch, merely ranged) but with no saving throw and able to attack objects. We liken it to a psychic hammerblow. He could have achieved the same effect by using burning ray)
On the other hand, another player dropped out of the game. He had a Monk1/Seer6, and he felt cheated because the sorcerer could make more powerful "Booms" than he could, and he would just fall further and further behind. Forget the fact that he had deliberately opimised his character for AC (Wis armour from monk, Inertial armour feat, Dex bonus, expertise, tumbling... he had the highest AC of any character and was the one who was least often in serious danger of dying). So he optimised heavily for one thing and then bitches because he can't be as good as the Sorcerer who is still wandering around in (roughly) AC13. Tough life eh?
(although seers get it a bit rough in terms of 9th level powers - their only choices all suck up xps to use!)
Cheers