There are a lot of alternative calendars around, for Muslims the current Islamic Year is 1435 A.H. anno Hegirae (in the year of the Hijra) and started on the 3rd of November 2013 (in the evening).
For Buddhists there are a number of different calendars but the most common gives the year as 2556 B.E. or Buddhist Era dated from the Buddha's death which according to various traditions was either the first full moon of May, April or June. Also the year is different according to the school of Buddhism being alternately 2140, 2556, 2557 or 2070.
According to the Jewish calendar it's 5774! The Bahá'í calendar makes it 170 but they also call it B.E. and it ends on the 20th 0f March. The Year consists of 19 Months of 19 days so goes out of sync quite quickly.