The closest I came was when cutting across the tracks and behind the dumpster leaving a friend's house in the wee hours of a coldish Boston morning, and as I came up the hill there were 2 rats (big fucking rats!) calmly heading towards the dumpster, and they hadn't seen me yet. I froze, so they didn't see me, and kept coming closer, and closer... I swear, I was a split second from throwing myself backwards off the embankment and trusting to luck that I'd miss the railroad tracks when they Saw Me! And Froze! And we stared at each other for what must have been THOUSANDS of milliseconds before they turned and ran.... I tell you, I still don't know who was more scared. But they obviously had more sense...