This is quite good, not even so much for the 'covers', but the naff titles/likely content:
http://kindlecoverdisasters.tumblr.com/
(Linked to from a Guardian piece on it.)
@Oliver Schick started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
This is quite good, not even so much for the 'covers', but the naff titles/likely content:
http://kindlecoverdisasters.tumblr.com/
(Linked to from a Guardian piece on it.)