Heavyweight

WBA - Nicolay Valuev
WBO - Shannon Briggs
WBC - Oleg Maskaev
IBF - Wladimir Klitschko
--------------------------------
Cruiserweight

WBA - O'neil Bell
WBO - Enzo Maccarinelli
WBC - O'Neil Bell
IBF - Krzysztof Wlodarczyk
--------------------------------
Light Heavyweight

WBA - Sylvio Branco
WBO - Zsolt Erdei
WBC - Tomasz Adamek
IBF - Clinton Woods
--------------------------------
Super Middleweight

WBA - Mikkel Kessler
WBO - Joe Calzaghe
WBC - Mikkel Kessler
IBF - Vacant
--------------------------------
Middleweight

WBA - Mariano Carrera
WBO - Jermain Taylor
WBC - Jermain Taylor
IBF - Arthur Abraham
---------------------------------
Super Welterweight

WBA - Jose Rivera - Travis Simms
WBO - Sergeii Dzinziruk
WBC - Oscar De La Hoya
IBF - Cory Spinks
---------------------------------
Welterweight

WBA - Miguel Cotto
WBO - Antonio Margarito
WBC - Floyd Mayweather
IBF - Kermit Cintron
---------------------------------
Super Lightweight

WBA - Souleymane M’baye
WBO - Ricardo Torres
WBC - Junior Witter
IBF - Juan Urango
---------------------------------
Lightweight

WBA - Juan Diaz
WBO - Acelino Freitas
WBC - Joel Casamayor - David Diaz
IBF - Jesus Chavez - Julio Diaz
---------------------------------
Super Featherweight

WBA - Edwin Valero
WBO - Joan Guzman
WBC - Marco Antonio Barrera
IBF - Malcolm Klaassen
---------------------------------
Featherweight

WBA - Chris John
WBO - Juan Manuel Marquez
WBC - Rudy Lopez
IBF - Vacant
---------------------------------
Super Bantamweight

WBA - Celestino Caballero
WBO - Daniel Ponce De Leon
WBC - Israel Vazquez
IBF - Steve Molitor
---------------------------------
Bantamweight

WBA - Wladimir Sidorenko
WBO - Jhonny Gonzalez
WBC - Hozumi Hasagawa
IBF - Rafael Marquez
---------------------------------
Super Flyweight

WBA - Nobuo Nashiro
WBO - Fernando Montiel
WBC - Masamori Tokuyama
IBF - Vacant
---------------------------------
Flyweight

WBA - Lorenzo Parra - Roberto Vasquez
WBO - Omar Narvaez
WBC - Pongsaklek Wonjongkam
IBF - Vic Darchinian
---------------------------------
Junior Flyweight

WBA - Koki Kameda
WBO - Hugo Cararez
WBC - Omar Niño
IBF - Ulises Solis
----------------------------------
Strawweight

WBA - Yukata Niida
WBO - Ivan Calderon
WBC - Eagle Kyowa
IBF - Muhammad Rachman



The ones in bold are divisions where one person has multiple titles, in my opinion these are the guys that sould be fighting each other, while I don't put much stock in the alphabet titles individually, when combined I think they are like Voltron.