I walked around the mall for 2 hours with my fly down.
Haha.. I'm sorry, that made me laugh a little bit. I do that sometimes too, and have no idea how I can forget so many times. I think at least if it happens, almost no one can really tell or notice, if that helps.
Unfortunately I had my shirt tucked in and I was wearing skinny jeans so everyone noticed they just didn't tell me.  I was wearing my superman undies too so it was extra noticeable...humiliating.
Well, you could have been going commando, too. And shame on them for not letting you know. Let's focus on the positives--you can pull off skinny jeans, and you're interesting enough to want to wear Superman underwear. Keep it up