Things I have, unwisely, read in the past week:
OMIM: Look at all the distressing things genetic material does! Biased heavily towards the awful, on the grounds that there are few case reports reading 'Probable diagnosis of rare genetic syndrome, one episode of mild symptoms, otherwise fine.' (Case series excepted.)
MMWR: Look at all the distressing things infectious diseases (and sometimes acute environmentally acquired terribleness) are doing this week! Read it and shudder, then go bleach everything!
Comment sections almost everywhere: Look at how terrible people are in the absence of social pressures to the contrary! (I recommend Ravelry instead, where complete strangers will put themselves out to be nice to fellow humans)