Steins;Gate - episode 7 - 17 May, 2011

After Daru updates the Phone Microwave's firmware, Okabe decides to perform an experiment attempting to change history by sending winning lottery numbers to the past. After Okabe sends the D-Mail, he experiences a sensation similar to the one he had before the satellite crash. Discovering noone else was aware that the experiment even took place, he finds his D-Mail had indeed led to Ruka purchasing a lottery ticket (though his own personal error led him to get the number wrong). After a brief encounter with Suzuha, Okabe deduces that a "world line shift" had occurred where the timeline changed to one where Ruka bought a lottery ticket on Okabe's advice, and Okabe had never performed the experiment in the first place, explaining everyone's altered memories. Confused as to why only he can remember the previous timeline, Okabe contacts Titor, who tells him he may have the power to become a messiah and lead the world beyond the "1% Divergence" point and hence, change the dystopian future. (Source: Wikipedia)