Roald Dahl's "Amanda and the Giant Agave"
By popular request (okay, only one, from the infamous Super Mellow Man), I am uploading a photo.
For reference, I am 5'6". These giant agave plants are a not-uncommon sight around here, but this one was bigger than most I've seen. These plants are really impressive when they're blooming, too - a giant tree basically shoots up out of the middle, probably 25-30 feet in the air. It's quite spectacular.
One thing about agave plants is that you don't want to get too close to them; the tips of their leaves are razor sharp and will literally cut you to the bone. I had a run-in with this plant's MUCH smaller cousin at our apartment complex a couple of years ago, and sustained a puncture would to my arm where I felt the spine hit my bone. It was gross, but otherwise uneventful. One of these guys would leave you gushing blood, that's for sure.