Note: The numbers in black are the prefilled numbers. The numbers in blue are the ones i have found out. The numbers written in small and grey are the possible numbers that can go in that particular box(as i have found out...there may be a mistake in that :) )
In the 8th column, the 7 has to be in the middle box, so it can be removed from the 9th row.
The really hard thing to see is that if the element in the 9th row and 8th column is 2, then either you cannot have any 2 in the 1st column, or in the 4th row. Hence this element has to be 1.
After that, the Sudoku is easily solved.