The Savior

Today is the mid of Sha'ban, the 15th day of the month of Sha'ban in the Islamic calendar. It is remembered by some Muslims, but for different reasons.
Most of Sunni Muslims believe that Mid-Sha'ban is a night of worship and salvation and it is commonly believed that during this night, Allah prepares the destiny for all people on Earth for the coming year. It's also believed that it is the night when the Qiblah - the direction that should be faced when a Muslim prays - was changed from Jerusalem (Al Aqsa Mosque) to Mecca (Kaaba). Prophet Ibrahim (Abraham) is the father of the prophets of the three main religions on Earth, however most of the prophets including Moses and Jesus (Peace be Upon them all) are chosen from Isaac's - Son of Ibrahim - branch. Prophet Muhammed (Peace be Upon Him) is - According to the Islamic point of view - the last prophet and he is chosen from Ismael's - other son of Ibrahim - branch. And I think the change of Qiblah towards Mecca - the place where prophet Muhammad was born and lived most of his life - is a symbol for that choice of prophet Muhammad as the final phrophet just as Mecca is the final destination of the Qiblah.
According to Shiia Muslims, it is also believed that on the 15th of Sha'ban, 255 AH (868 CE), Muhammad al-Mahdi was born. The concept of the presence of a chosen person who will save human kind, and achieve justice for the whole world is found in all religions and beliefs. However the personality of that chose person deffers from one religion to another.
In Judaism and Jewish eschatology, the Messiah ("anointed [one]") has traditionally referred to a future Jewish king from the Davidic line who will be "anointed" with holy anointing oil and inducted to rule the Jewish people during the Messianic Age. But later on when Prophet Issa (Jesus) was born, Jews believe that Jesus was wrong and wanted to kill him. May be because he didn't meet the specification they wanted him to have. And may be because they found themselves going to loose some privelages that they used to have if they believed in him.
Christians on the other hand belive that Jessus will come back and he is going to be their Saviour or The chosen one.
Muslims have different views of the Saviour, most of Sunni and Shiiy Muslims belive that he is The Mahdi, however Shiits belive that the Mahdi is the Twelve's Imam and he is already born, while Sunnis believe that he is not born yet. Some other Sunni groups belive that Prophet Issa (Jesus) is going to be the one and he is the Mahdi according to their point of view.
Even in a movie such as The Marix triology, a messianic figure referred to as "The One" was featured by Neo. In The Matrix, The One is described this way by the character of Morpheus: "When the Matrix was first built, there was a man born inside who had the ability to change whatever he wanted, to remake the Matrix as he saw fit. It was he who freed the first of us, taught us the truth. As long as the Matrix exists the human race will never be free".
According to these different views and expectations of the chosen one, people are going to choose different sides to fight with during the last battel - Armageddon - where each team is going to belive that he is on the right side. According to our point of view as Muslims, Prophet Issa (Jessus) is going to join Al Mahdi in his fight and that why it is belived that Muslims and Christians are going to fight on the same side. On the other hand, Jews who did not belive Jesus earlier and wanted to kill him, are expected to fight him later on too. And may be that's why Allah said in the Quran that Christans are the ones who are close to Muslims while Jews are their enemies.

Sources:
Wikipedia, Mid-Sha'ban
Wikipedia, Mahdi
Wikipedia, Muhammad al-Mahdi
Wikipedia, Salvation
Wikipedia, Qibla
Wikipedia, Messiahs in fiction
Wikipedia, Messiah
Wikipedia, Jewish eschatology
Wikipedia, Jewish Messiah

PS. For Jewish and Christian readers, the knowledge in this article is heavily depending on Wikipedia, and I may be biased to the Islamic point of view some how, so if they find anything wrong here please comment on it.

Tags: Shaaban, Islam, Christianity, Judaism, Theology, Savior, Mahdi, Salvation, Sunna, Shiia, Messiah, The Matrix, Armageddon, Gr33n Data