This is a great way to challenge yourself as a designer.
Johnny Selman made a pledge to design one poster a day about a headline in world news. He began this as his graphic design thesis project and continued to expand as he realized his impact in visually presenting important information to the masses. His posters are really great executions of concept- interesting and easily understood.
See what Steven Heller has written on his blog http://imprint.printmag.com/daily-heller/poster-a-day-a-visual-vitamin/
and Johnny Selman’s website http://bbcx365.com/