Aluminum is nice, and light but can "bite" you right in the a** literally! While coming back from a Walmart shopping trip, I rode over a dip in the bike lane about a half mile away from home, and all of a sudden, I found myself falling back away from my folder, and landed on my back while the bike rolled on it's own for about 10 feet and fell on the left side.
I quickly got up, and ran to the bike to pick it up. At first I thought that the suspension had broken or something, but to my surprise, it was the seat post that had snapped! I also had to pick up my cyclometer which had fallen off in the middle of the street.
Since I was close to home, I was able to ride the bike the rest of the way by standing on the pedals. The only "injury" if you can call it that was to my ego, and I did cut two of my finger tips but not so bad as I can type this message with no discomfort.
Here are some photos of the breakage:
In retrospect, I should have known better, as I had seen a couple of "nicks" on the seat post just above the frame. The frame is steel, and indestructible! It'll be still be around by the time I start collecting social security.