I have posted special Conference Room chat topic for this weekend in hono(u)r of this weekend's WWI centenary.  

See the Meta question [Conference Room chat: WWI centenary and finding records about WWI service members][1] for details about special online events and free access weekends.  To encourage people to write up their questions and findings, I'd like to suggest finding WWI records and relatives as a topic challenge.

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A "Gallipoli edition" of this answer ran as a Topic Challenge in the weeks leading up to its 100th anniversary on 25 Apr 2015: https://genealogy.meta.stackexchange.com/questions/2004/ask-your-anzac-ancestry-questions-on-100th-anniversary-of-gallipoli-landing
but there is plenty of scope to re-run this challenge as 100th anniversaries of other battles loom (feel free to add more):

 - Verdun February-December 1916
 - Somme July-November 1916
 - Ypres July-November 1917
 - Caporetta October-November 1917
 

  [1]: https://genealogy.meta.stackexchange.com/questions/1918/conference-room-chat-wwi-centenary-and-finding-records-about-wwi-service-member