Renaming multiple files with SED

for file in *.htm ; do mv $file `echo $file | sed 's/\(.*\.\)htm/\1html/'` ; done

For loop to rsync some files

Copy over each file beginning blegga containing number between 516 to 524 and ending with avi

for (( i = 516; i < 525; i++)); do rsync -P blegga*$i*.avi moo:foo/; done