Myspace and Tumblr this week emerged as the latest in a string of mega breaches that resulted in the theft of millions of user IDs -- not just recently but years ago. "Over the period of this month, we've seen an interesting trend of data breaches," wrote security researcher Troy Hunt, operator of the Have I Been Pwned website. "Any one of these four I'm going to talk about on their own would be notable, but to see a cluster of them appear together is quite intriguing."