I grabbed a load of Bruce Doscher's TdF posters [1] from his Facebook feed, monkeyed around with them a bit to fit, and have a script that rotates them every 10 mins or so. I also use them as the screensavers on my Kindle.
[1] http://www.cyclingshorts.uk.com/2011/07/18/bruce-doscher-cycling-poster-prize-draw/
[1] http://www.cyclingshorts.uk.com/2011/07/18/bruce-doscher-cycling-poster-prize-draw/