I used to get this when Bleachbit refused to start (crash):

username@computer:~$ gksu bleachbit
info: starting BleachBit version 0.8.7
debug: chown(/root/.config/bleachbit/bleachbit.ini, uid=1000)
    from Cleaner import backends
  File "/usr/share/bleachbit/bleachbit/Cleaner.py", line 44, in <module>
    import Special
  File "/usr/share/bleachbit/bleachbit/Special.py", line 27, in <module>
    from Options import options
  File "/usr/share/bleachbit/bleachbit/Options.py", line 246, in <module>
    options = Options()
  File "/usr/share/bleachbit/bleachbit/Options.py", line 44, in __init__
    self.restore()
  File "/usr/share/bleachbit/bleachbit/Options.py", line 149, in restore
    self.set_list('shred_drives', Unix.guess_overwrite_paths())
  File "/usr/share/bleachbit/bleachbit/Options.py", line 195, in set_list
    self.__flush()
  File "/usr/share/bleachbit/bleachbit/Options.py", line 62, in __flush
    General.chownself(Common.options_file)
  File "/usr/share/bleachbit/bleachbit/General.py", line 76, in chownself
    assert(path.find('/root') != 0)
AssertionError
username@computer:~$

Now, Bleachbit dosn't crash:
Username@computer:~$ gksu bleachbit
info: starting BleachBit version 0.8.7
info: automatically preserving language 'en'
info: automatically hiding cleaner 'adobe_reader'
info: automatically hiding cleaner 'amsn'
info: automatically hiding cleaner 'amule'
info: automatically hiding cleaner 'audacious'
info: automatically hiding cleaner 'bash'
info: automatically hiding cleaner 'beagle'
info: automatically hiding cleaner 'chromium'
info: automatically hiding cleaner 'd4x'
info: automatically hiding cleaner 'easytag'
info: automatically hiding cleaner 'elinks'
info: automatically hiding cleaner 'emesene'
info: automatically hiding cleaner 'epiphany'
info: automatically hiding cleaner 'evolution'
info: automatically hiding cleaner 'exaile'
info: automatically hiding cleaner 'filezilla'
info: automatically hiding cleaner 'firefox'
info: automatically hiding cleaner 'flash'
info: automatically hiding cleaner 'gedit'
info: automatically hiding cleaner 'gftp'
info: automatically hiding cleaner 'gimp'
info: automatically hiding cleaner 'gl-117'
info: automatically hiding cleaner 'gnome'
info: automatically hiding cleaner 'google_chrome'
info: automatically hiding cleaner 'google_earth'
info: automatically hiding cleaner 'google_toolbar'
info: automatically hiding cleaner 'gpodder'
info: automatically hiding cleaner 'gwenview'
info: automatically hiding cleaner 'hippo_opensim_viewer'
info: automatically hiding cleaner 'java'
info: automatically hiding cleaner 'kde'
info: automatically hiding cleaner 'konqueror'
info: automatically hiding cleaner 'liferea'
info: automatically hiding cleaner 'links2'
info: automatically hiding cleaner 'midnightcommander'
info: automatically hiding cleaner 'miro'
info: automatically hiding cleaner 'nautilus'
info: automatically hiding cleaner 'nexuiz'
info: automatically hiding cleaner 'openofficeorg'
info: automatically hiding cleaner 'opera'
info: automatically hiding cleaner 'pidgin'
info: automatically hiding cleaner 'realplayer'
info: automatically hiding cleaner 'recoll'
info: automatically hiding cleaner 'rhythmbox'
info: automatically hiding cleaner 'screenlets'
info: automatically hiding cleaner 'seamonkey'
info: automatically hiding cleaner 'secondlife_viewer'
info: automatically hiding cleaner 'skype'
info: automatically hiding cleaner 'thunderbird'
info: automatically hiding cleaner 'transmission'
info: automatically hiding cleaner 'tremulous'
info: automatically hiding cleaner 'vim'
info: automatically hiding cleaner 'vlc'
info: automatically hiding cleaner 'vuze'
info: automatically hiding cleaner 'wine'
info: automatically hiding cleaner 'winetricks'
info: automatically hiding cleaner 'x11'
info: automatically hiding cleaner 'xchat'
info: automatically hiding cleaner 'xine'
info: automatically hiding cleaner 'yum'
Username@computer:~$