I already had profiles for each of the tools explored in Thing 6, (LinkedIn, academia.edu and ResearchGate), but this prompted me to update them as well as look more closely at each.
LinkedIn is good as an online CV, and good for connecting in industry as well as in academia. I feel this is useful for those of us who bridge that gap.
ResearchGate and academia.edu seem quite similar to me, and I have used both to download papers and find connections which have been useful to my research. Some of the emails I receive from them are not particularly useful – I get a lot of alerts for jobs to which I am not suited from ResearchGate, and academia.edu’s digest of uploaded papers that match my research interests rarely throws up anything useful or even related to my study.