rename

To rename all files matching *.bak to strip the extension,
rename 's/\e.bak$//' *.bak
To translate uppercase names to lower,
rename 'y/A-Z/a-z/' *
To fix the extension of html files (from .htm to .html)
rename .htm .html *.htm
To check what will be renamed first BEFORE actually renaming
rename -n 's/current_name/new_name/' More examples:

rename 's/\.flip$/.flop/'       # rename *.flip to *.flop
rename s/flip/flop/             # rename *flip* to *flop*
rename 's/^s\.(.*)/$1.X/'       # switch sccs filenames around
rename 's/$/.orig/ */*.[ch]'    # add .orig to source files in */
rename 'y/A-Z/a-z/'             # lowercase all filenames in .
rename 'y/A-Z/a-z/ if -B'       # same, but just binaries!
rename chop *~                  # restore all ~ backup files