Finding the directory which uses most space in a File System

                                                    du -sk * | sort -rnk 1,1 | more

-> This will fetch the top directory in terms of space utilization in the current directory and display in descending order.
-> This might take some time in displaying the o/p if the content in the directory is huge.
-> 'du' displays the size of the file space allocated to, and the size of the file space allocated to each subdirectory.