Erik Morales - He won another world title. Floyd Mayweather - Continued to be the best. Vitali Klitschko - See Erik Morales.
Foreman for obv reasons. Morales was succesful despite being obviously being barely half of what he was. Tyson had a lot of succes along with Ali after there 3 year gaps from the sport
George Foreman came back to win the title 17 years after he last held it. Ray Leonard made multiple comebacks with different results in one he was successful beating Marvelous Marvin Hagler for the Middleweight crown the last one was a complete failure losing and taking a one sided beating from Terry Norris and getting stopped by Camacho. Eder Jofre - Retired after his second defeat to Harada and came back three years later fighting one division above at 126 notching a 25 -0 record and winning the WBC featherweight crown from Jose Legra. Ray Robinson- retired after losing to Joey Maxim and came back three years later to become a three time MW Champion.
http://boxrec.com/list_bouts.php?cat=boxer&human_id=5625 Harry Simon, former WBO 160 champ (who beat Winky Wright before his trademark Ghanian defence) spent two stints in jail and did not fight between 2001 and 2007. He has only beaten journeymen since returning, but I think when you look at what he went through you have to consider it a success. Undefeated as well. Defended his world title in different countries. Good fighter, I hope he either steps it up soon or keeps fighting guys he can win against and cash in some paper at the age of 40.
Well, Arguello retired when he was very young, so if you count his career from 130lbs onwards as a "comeback", his would surely be the best ever?
Manny Pacquiao. After JMM 2 he was considered done with the sport but magically Ariza came into the picture and Manny became FOTD. Now that he's back to "ordinary" Pacquiao he's considerred done yet again.