Forget swine flu, it's nephila clavata (무당거미) season. Those three---two females and a male---were hanging out *cough* near the entrance of Chonnam National University last week, as was this one:
Here are a couple photographs I took in Beolgyo-eup, Boseong county a couple of years ago. You'll find one of the pictures on Wikipedia
When they reach maturity their bodies are roughly eight feet long and 600 pounds, and they live in colonies of up to 1,000.