Rsync

rsync -P rsync://rsync.server.com/path/to/file file Only get diffs. Do multiple times for troublesome downloads

rsync --bwlimit=1000 fromfile tofile

Locally copy with rate limit. It's like nice for I/O

rsync -az -e ssh --delete ~/public_html/ remote.com:'~/public_html'

Mirror web site (using compression and encryption)

rsync -auz -e ssh remote:/dir/. && rsync -auz -e ssh. remote:/dir/

Synchronize current directory with remote one