Trending: Selfies at serious places, selfies at funerals...
Is a selfie at a funeral a step too far? What about a selfie at a Holocaust memorial? Or outside a raging house fire?
These are all real examples from two Tumblr sites - Selfies at Serious Places and, a new site, Selfies at Funerals - set up by New Yorker Jason Feifer. His examples are all collated from publicly accessible images posted on social networks. One of them reads "shirtless, homeless bum selfie", and shows a young man making a V sign in front of a rough-looking man, slumped on the ground in Las Vegas.
"What you're seeing is an expression of one second's worth of thought... it's an impulse," says Feifer.
Selfies are photos taken by oneself, of oneself. The internet is bursting with these iterations of me, me, me - more than 53 million pictures have been tagged #selfie on the photo-sharing site Instagram. Mobile phones now come with cameras specially designed for the arm's length selfie shot. Feifer got thinking about the backdrop people use for selfies while on holiday with his wife in Europe. As they toured sites like Anne Frank's house in Amsterdam or the Holocaust Memorial in Berlin, he kept noticing people whipping out their phones for a quick pose.
About BBC Trending
Some people whose photos are featured on the site have written to Feifer to say they feel embarrassed for taking the selfies where they did - others to justify themselves, or say the pictures have been used out of context. Feifer says he's not trying to judge anyone - people often just want a record of where they have been. But he does think it's an interesting social phenomenon.
"This is a thing that people do - and when you see it in aggregate it takes on a meaning. For the first time in human history, we have the ability to share whatever we see, whenever we see it," he says. "We are still figuring out what value that is, and what is supposed to be shared - maybe everything should be shared, maybe nothing should be shared."
Reporting by Cordelia Hebblethwaite
Have you spotted an interesting trend? Tweet us using #BBCtrending