I did that too, but not for fun... the up/down escalators weren't right next to each other... the upwards one was on the other side of the mall, and I went down the downwards one, before realizing I should have stayed upstairs... so rather than go all around the mall, I just ran back up the escalator. I have long legs, so it was fast.

No one else was on the escalator except me and my friend, though, or else I wouldn't have done it. I assume it must be dangerous (and rude) with other people on it.

It was hilarious, though, because I was with my friend, and once I was already up the stairs, I saw she wasn't with me...

I looked down, and she was jogging like a treadmill somewhere in the middle of the escalator, laughing her ass off because she couldn't go up fast enough and she was stuck. She was laughing so hard I couldn't even hear her at first until she gasped for air. Needless to say, I started cracking up pretty hard too.

For a good ten minutes afterwards, while we were walking through the mall, we were still laughing with tears running down our cheeks.