Whilst this argument has been stated previously (C.S. Lewis formed the first version with only three L's, and Legend was added later), I feel it is well worth repeating. This is essentially an argument as too who the real historic figure of Jesus of Nazareth was. There is extensive historical documents surrounding this Rabbi from Judea who claimed to be much more than just a Rabbi. (Don't believe me that Jesus claimed to be God? See Matt. 27:43, Mark 14:62, Luke 22:70, John 6:35, John 6:40, John 6:51, John 8:12, John 8:23-24, John 8:58, and a bunch of others that I couldn't be bothered to look up right now)
There are essentially four possibilities as to who Jesus was based on these documents: Legend, or these account are heavily if not entirely fictionalized; Liar, or Jesus was a masterful Charlatan, perhaps with some form of demonic or magical power; Lunatic, Jesus was insane; or Lord, Jesus is the rightful Lord and ruler of your life. Essentially Jesus of Nazareth must be one of these four things, or some combination thereof. Now lets examine each of these in order:
Legend
Now this one is the most popular and consists of two main variants. First, Jesus did not exist at all, which doesn't make sense from a historic perspective, the shear quantity of documentation about him proves, as near as can be done with any historic figure, that Jesus of Nazareth existed. Now of course the more popular form is almost definitely that Jesus did exist, but that is no more reliable most scholars place the original authorship of the New Testament within the life span of the people who actually met Jesus. Just imagine if a bunch of Martin Luther King's supporters started to make those sort of claims about him today. It doesn't make sense.
Liar
Basically this requires Jesus to have been such an expert liar that he actually managed to convince a large number of people that he rose people from the dead, several times, and even feed thousands of people magically, again several times. Managing to trick people into believing in these miracles is a miracle in and of itself. And then of course there's the little question of how many liars are willing to die for their lies?
Lunatic
Of course he might still be crazy, except of course that the thousands of people who met him in his life appear not to have thought so, after all they where apparently quite impressed with him, so much so that leaders in society came to him for help on several occasions. Also crazy doesn't grant the power to perform miracles as far as I know.
Lord
And that leaves our third and final possibility. So, who do you think Jesus was?