These are some patches I wrote in the past.

mailman_hide_email.patch         - mask email addresses by john.doe at xxxxx
pan_google_link.patch            - add menu item "Read at Google" to Pan's message popup menu
phpbb_dfde_forum2mail.patch      - patch to send every post in a phpbb forum to a mailing list(including References: header for sorting)
pokerth_fullscreen.patch         - add fullscreen mode to PokerTH (see http://www.pokerth.net/)
scintilla_bash_folding.patch     - simple patch to fix folding in Scintilla's Bash lexer
sylpheed_mark_all.patch          - add menu item "Mark all read" to Sylpheed's folder popup menu
sylpheed_set_as_junk.patch       - add menu item "Set as [not] junk mail" to Sylpheed's message popup menu

The following ones are already applied by the upstream authors (thanks):
- phpbb_dfde_forum2mail.patch
- pokerth_fullscreen.patch
- scintilla_bash_folding.patch
- sylpheed_mark_all.patch
- sylpheed_set_as_junk.patch

Index of /patches/