As 2017 wheezes to its merciful end and the social media titans reckon with growing backlash, Twitter's largely forgotten video streaming app Periscope has gained an insidious second life as a hub for seekers of child pornography. Gizmodo's search of the platform over the course of a single afternoon uncovered dozens of accounts - 50 in total - which appeared to be soliciting sexualised images of minors, or in the worst cases, depicting it themselves.