When you are using rsync to copy/synchronize files from A to B it's very useful to know that it's possible to set a Bandwidth Limit. This is very nice for remote backups so your internet connection won't be 'choked'

Take a look at this video explaining it:

Or if you just want the command:

rsync --stats --progress --bwlimit=750 -auv /FolderA /FolderB