I've broken Dungeons & Dragons 4th Edition with the following build. I call it the "Psionic Bomber".
BUILD: Shaper Psion
Required Level: 2.
+ Static Mote
+ Dimensional Scramble
+ Daily 1: Living Missile
+ Daily Utility: 2: Telekinetic Lift
+ Hedge Wizard's Gloves
+ Bag: in which to place dirt
+ 1: Discipline Adept
+ 2: Vicious Advantage
+ 1: Mordenkainen's Disk.
The basic concept of the bomber is to create a class that maximizes, in a most obscene fashion, the generally unused third dimension of the game. The idea is to drop objects on enemies to devastate them quickly and efficiently. The attack used is not a traditional power, but one house-ruled to accomodate this ballistic approach.
Dropping items from a height is a simple attack, used by defenders in their towers for centuries. A creative use of arcane and psionic powers makes for a much more mobile, aggressive approach.
Bombing attacks utilize the following power.
Attack: Intelligence VS Reflex
Target: Any creatures under the boulder, be the boulder medium or large, depending on materials.
Hit: The Target(s) take(s) 1 D10 per 2 squares dropped. (A maximum-altitude boulder will render 15D10 falling damage to a target!)
Miss: the target must move 1 square to get out of the way (not shifting, possibly provoking attacks of opportunity) or takes half damage.
Simple bombing attack:
Using Mage Hand to grasp an unattended rock or other blunt object (a minor action) and lift it up and over to 5 squares (a movement action) then drop said item (a free action) the "Bombs Away!" attack ought to be able to be made, with 2D10 damage possible on flat ground.
Simple group attack:
Prepare by using Static Mote's auto-slowing of adjacent creatures, and utilize the feat Vicious Advantage's benefit of Combat Advantage; cripple your enemies and then hurl them into the air with Dimensional Scramble, causing an additional D10 of falling damage to anyone who fails their save against the teleportation, or will knock them prone if they manage to resist the forced teleportation.
Use Telekinetic Lift to carry boulders up to 400lbs into the sky; using SHAPED CONSCIOUSNESS up to twice to extend the range of the Telekinetic Lift when needed. Proceed as follows: manifest your Shaped Consciousness, then use that manifestation to manifest Shaped Consciousness again, up into the air both times, for a maximum vertical altitude of 20 squares. Given that Telekinetic Lift's massive altitude is 10, the combined range grants you 30 squares of altitude on this if you are standing flat on the ground. Bombs away!
Multi Massive attack:
As above, and add the Minor Creation's ability to conjure out of thin air two treasure chests that plummet downwards at a rate of 100 squares per turn, which last for 5 minutes each, though I surmise they are destroyed upon impact. That means that when you release your Telekinetic Lift's target, you can add two extra minor-action attacks to the mix.
Place the bag of dirt under the disk, stand on the disk, levitate the dirt using Mage hand, keeping it under your Mordenkainen's Disk to ensure smooth aerial travels. Use Telekinetic Lift to carry boulders up to 400lbs into the sky; using SHAPED CONSCIOUSNESS up to twice to extend the range of the Telekinetic Lift when needed. When you have arrived at the desired altitude, destroy anything. Combine with Minor Creation treasure chest bombs and you can kill anything you hit.
I hope you have found this to be insightful.