This is my OU team so far. Sorry for not being as descriptive as possible but here goes..
***UPDATE*** 7-17-11
Swampert @ Leftovers
Torrent
Relaxed
EV: 240 HP / 216 Def / 52 Sp Def
Roar
Ice Beam
Earthquake
Stealth Rock
Thanks to Eternal for the suggestion, I have incorporated him in my team as a Stealth Rock Supporter and to Check Thunderus and to be an overall tank to my team. He can also phaze set up sweepers who would otherwise sweep my entire team. With Toxic Spikes and Roar he will be able to poison every grounded pokemon and any non-steel type.
PURPOSE: He is to set up Stealth Rocks and to wall Thundurus and phaze him out by using Roar and to get residual damage on incoming pokemon. He is also able to take a few hits and return the damage.
Conkeldurr @ Leftovers
Adamant
EV: 120 HP / 252 Atk / 136 Sp Def
Guts
Bulk Up
Drain Punch
Mach Punch
Payback
With all the entry hazards, he can set up a Bulk Up while minimal damage and start a sweep. He is one of my three sweepers and is able to do the job. I can bring him in when a pokemon fires a Scald amied at X pokemon and it is not a problem Conkeldurr gets burned because of Guts. Then I can follow with a sweep.
PURPOSE: With two Bulk Ups Conkeldurr is a force to be reckoned with and can be a vital late game sweeper. With aid from the entry hazards, he will be able to score important OHKOs.
Latios @ Expert Belt
Timid
EV: 252 Sp Atk / 4 Sp Def / 252 Spe
Levitate
Draco Meteor
Surf
Hidden Power (Fire)
Thunder Bolt
You can say this is my "Special" sweeper. He is a potent sweeper as he has very high Speed and Sp Atk. I can switch back and forth between him and Conkeldurr because Latios can take his Psychic weakness and Conkeldurr takes his Dark weaknesses.
PURPOSE: He is a sweeper intended for pokemon that have low Sp Def. His moveset allows for neutral coverage and to "surprise" X pokemon to hit them with another attack for superior damage.
Gliscor @ Toxic Orb
Impish
EV: 252 HP / 184 Def / 72 Spe
Poison Heal
Protect
Earthquake
Substitute
Ice Fang
This is a bulky Sweeper aimed to status stall and to finish the opposing pokemon off with an appropriate attack. With this EV spread, he is able to set up and Sweep. I can use Swampert's Stealth Rock support and Forretress' Toxic Spikes support and help him out with the sweep. Thanks to Eternal for the suggestion I have replaced SD with Protect to stall and then kill.
PURPOSE: He sweeps/stalls the opposing team and is a decent wall overall as he can take on opposing Conkeldurr and Thundurus to an extent.
Forretress @ Leftovers
Relaxed
EV: 252 HP / 176 Def / 80 Sp Def
Sturdy
Toxic Spikes
Spikes
Rapid Spin
Gyro Ball
He is my "utility" pokemon as he can Wall,Set Up, and Spin-Away. He takes physical hits pretty well and he is able to take some hits on the special side too. The reason I have him is to set up my entry hazards and spin away the opponents. His Gyro Ball allows him to hit anything that does not resist him for a decent amount of damage.
PURPOSE: To spin away entry hazards and to set up my own. Also to wall or sponge physical attacks.
Milotic @ leftovers
Bold
EV: 252 HP / 252 Def / 4 Sp Atk
Marvel Scale
Scald
Ice Beam
Recover
Dragon Tail
She is my go to pokemon when I'm in a pinch and she can just Dragon Tail set up sweepers who would other wise not take damage from her attacks. She is very bulky and she can dish out some nice damage to fire types and dragon types.
PURPOSE: She is used to stop sweepers from setting up and to perhaps get a Burn or a Freeze off and then go to Gliscor.
***UPDATE*** 7-17-11
Swampert @ Leftovers
Torrent
Relaxed
EV: 240 HP / 216 Def / 52 Sp Def
Roar
Ice Beam
Earthquake
Stealth Rock
Thanks to Eternal for the suggestion, I have incorporated him in my team as a Stealth Rock Supporter and to Check Thunderus and to be an overall tank to my team. He can also phaze set up sweepers who would otherwise sweep my entire team. With Toxic Spikes and Roar he will be able to poison every grounded pokemon and any non-steel type.
PURPOSE: He is to set up Stealth Rocks and to wall Thundurus and phaze him out by using Roar and to get residual damage on incoming pokemon. He is also able to take a few hits and return the damage.
Conkeldurr @ Leftovers
Adamant
EV: 120 HP / 252 Atk / 136 Sp Def
Guts
Bulk Up
Drain Punch
Mach Punch
Payback
With all the entry hazards, he can set up a Bulk Up while minimal damage and start a sweep. He is one of my three sweepers and is able to do the job. I can bring him in when a pokemon fires a Scald amied at X pokemon and it is not a problem Conkeldurr gets burned because of Guts. Then I can follow with a sweep.
PURPOSE: With two Bulk Ups Conkeldurr is a force to be reckoned with and can be a vital late game sweeper. With aid from the entry hazards, he will be able to score important OHKOs.
Latios @ Expert Belt
Timid
EV: 252 Sp Atk / 4 Sp Def / 252 Spe
Levitate
Draco Meteor
Surf
Hidden Power (Fire)
Thunder Bolt
You can say this is my "Special" sweeper. He is a potent sweeper as he has very high Speed and Sp Atk. I can switch back and forth between him and Conkeldurr because Latios can take his Psychic weakness and Conkeldurr takes his Dark weaknesses.
PURPOSE: He is a sweeper intended for pokemon that have low Sp Def. His moveset allows for neutral coverage and to "surprise" X pokemon to hit them with another attack for superior damage.
Gliscor @ Toxic Orb
Impish
EV: 252 HP / 184 Def / 72 Spe
Poison Heal
Protect
Earthquake
Substitute
Ice Fang
This is a bulky Sweeper aimed to status stall and to finish the opposing pokemon off with an appropriate attack. With this EV spread, he is able to set up and Sweep. I can use Swampert's Stealth Rock support and Forretress' Toxic Spikes support and help him out with the sweep. Thanks to Eternal for the suggestion I have replaced SD with Protect to stall and then kill.
PURPOSE: He sweeps/stalls the opposing team and is a decent wall overall as he can take on opposing Conkeldurr and Thundurus to an extent.
Forretress @ Leftovers
Relaxed
EV: 252 HP / 176 Def / 80 Sp Def
Sturdy
Toxic Spikes
Spikes
Rapid Spin
Gyro Ball
He is my "utility" pokemon as he can Wall,Set Up, and Spin-Away. He takes physical hits pretty well and he is able to take some hits on the special side too. The reason I have him is to set up my entry hazards and spin away the opponents. His Gyro Ball allows him to hit anything that does not resist him for a decent amount of damage.
PURPOSE: To spin away entry hazards and to set up my own. Also to wall or sponge physical attacks.
Milotic @ leftovers
Bold
EV: 252 HP / 252 Def / 4 Sp Atk
Marvel Scale
Scald
Ice Beam
Recover
Dragon Tail
She is my go to pokemon when I'm in a pinch and she can just Dragon Tail set up sweepers who would other wise not take damage from her attacks. She is very bulky and she can dish out some nice damage to fire types and dragon types.
PURPOSE: She is used to stop sweepers from setting up and to perhaps get a Burn or a Freeze off and then go to Gliscor.