Very simple command, more for maintenance and cleaning up, use it all the time to clean up orphaned log files that take up space
Change the head number to increase the number of files. This will output the biggest files in a directory and its subdirectories.
I realize I may be telling you how to suck eggs, but some may not know it but need it
find /path/to/dir/ -printf '%s %p\n'| sort -nr | head -10
find . -printf '%s %p\n'| sort -nr | head -10