The time period of Odysseus is obviously completely unlike today and probably very unrealistic.  During those times it probably was acceptable to take one's own revenge to a certain extent.  The book is entirely based on revenge and it shapes the way all the characters act.  It seems every action is spurred from the need for revenge.  I'm not even sure that I neccessarily agree with it in the book.  In the slaughtering of the suitors, there were some who regreted what they had done but they still had to die because "Athen destined them to die".  I think that what Odysseus did was too strong a reaction, which is the major problem with doing things yourself.  When someone has wronged you, your judgement becomes clouded.  Revenge never works appropriately.  Often times, the punishment is worse than the crime.  This just sets off a chain reaction that doesn't solve anything.  An example of this is the fathers of the suitors who wanted to attack Odysseus because he killed their sons.  For revenge to be actual justice, the punishment of the person who committed the crime should be decided by a group of impartial people.  Odysseus' style of revenge would obviously not work today.  If someone had a relative who was murdered by someone and then they went out and found the killer and killed them, they would still go to jail.  It's wrong to be the "vigilante".  It's not really justice at all.  I don't think that justice can ever be put into the hands of just one person for them to decide.  You have to do what is fair.