This ignorelist can be used to backup your home folder without useless folders and files, see http://askubuntu.com/a/545676/34298

ignorelist

#These directories may be excluded:

# contains mounted file systems
.gvfs
.local/share/gvfs-metadata
# contains the actual encrypted home directory
.Private
# session-specific
.dbus
.cache
.Trash
.local/share/Trash
# cached info about audio CDs
.cddb
# cached packages lists
.aptitude

#Flash-specific:

# Cache for flash, maybe others?
.adobe
# except for Flash persistence, there is no reason to keep this
.macromedia

#Files:

# contains errors from the current graphical session
.xsession-errors
# recently used files
.recently-used
.recently-used.xbel
.thumbnails
# session-specific
.Xauthority
.ICEauthority
.gksu.lock
.pulse  # directory
.pulse-cookie
.esd_auth

#KDE specific:

# Recent documents on KDE
.kde/share/apps/RecentDocuments
# Contains a history of the Klipper clipboard (KDE)
.kde/share/apps/klipper
# you will loose saved scrolling positions of PDFs
.kde/share/apps/okular/docdata
.kde/share/apps/gwenview/recentfolders
# cached other users' profile pics
.kde/share/apps/kmess/displaypics
# cached emoticons of others
.kde/share/apps/kmess/customemoticons

#Firefox-specific (see also Profile folder):

.mozilla/firefox/*/Cache
# in case Fx crashes dumps will be stored in this
.mozilla/firefox/*/minidumps
# session-specific 
.mozilla/firefox/*/.parentlock
# phishing database, recreated
.mozilla/firefox/*/urlclassifier3.sqlite
# blacklisted extensions
.mozilla/firefox/*/blocklist.xml
# extension database, recreated on startup
.mozilla/firefox/*/extensions.sqlite
.mozilla/firefox/*/extensions.sqlite-journal
.mozilla/firefox/*/extensions.rdf
.mozilla/firefox/*/extensions.ini
.mozilla/firefox/*/extensions.cache
# cached UI data, recreated
.mozilla/firefox/*/XUL.mfasl
.mozilla/firefox/*/XPC.mfasl
.mozilla/firefox/*/xpti.dat
.mozilla/firefox/*/compreg.dat

#Opera-specific (related question on Superuser.com: Is documentation available on files and directories in the Opera profile folder?):

.opera/temporary_downloads
.opera/cache
.opera/thumbnails
.opera/opcache
.opera/icons
.opera/application_cache
.opera/widgets/*/cache
.opera/lock

#Komodo Edit:

.komodoedit/*/codeintel/db
.komodoedit/*/host-*/*/codeintel
.komodoedit/*/XRE/Cache
.komodoedit/*/XRE/.activatestate/komodo edit/Crash Reports
.komodoedit/*/XRE/.activatestate/komodo edit/*/Cache
.komodoedit/*/XRE/.activatestate/komodo edit/*/minidump
.komodoedit/*/XRE/.parentlock
.komodoedit/*/XRE/extensions.rdf
.komodoedit/*/XRE/extensions.ini
.komodoedit/*/XRE/extensions.cache
.komodoedit/*/XRE/XPC.mfasl
.komodoedit/*/XRE/XUL.mfasl
.komodoedit/*/XRE/xpti.dat
.komodoedit/*/XRE/pluginreg.dat
.komodoedit/*/XRE/compreg.dat
.komodoedit/*/XRE/*.sqlite-journal
.komodoedit/*/pystdout.log
.komodoedit/*/pystderr.log
.komodoedit/*/history.sqlite.bak
.komodoedit/*/running.lock
.komodoedit/*/mutex.lock
.komodoedit/*/*.xmlc
.komodoedit/*/startup-env.tmp
.komoeoedit/*/commandments.fifo
.komoeoedit/*/history.sqlite

#GnuPG:

.gnupg/rnd
.gnupg/random_seed
.gnupg/.#*
.gnupg/*.lock
.gnupg/gpg-agent-info-*

#Chromium:

.config/chromium/Default/Local Storage
.config/chromium/Default/Session Storage
.config/chromium/Default/Application Cache
.config/chromium/Default/History Index *

#Google Chrome:

.config/google-chrome/Default/Local Storage
.config/google-chrome/Default/Session Storage
.config/google-chrome/Default/Application Cache
.config/google-chrome/Default/History Index *

#Other apps:

# Pidgin
.pulse/icons
# Cached applets
.java/deployment/cache
.icedteaplugin
.icedtea
.gnome2/epiphany/favicon_cache

the repository has moved to github

https://github.com/rubo77/rsync-homedir-excludes/blob/master/rsync-homedir-excludes.txt