DR RLP--I can relate. I travel a lot and never know what fun experience I'll have trying to get my held mail from the Post Office. I usually state on the online form that I will pick up the mail, but sometimes it's delivered on the last day and the mail's all crammed into my mailbox.
About a 6 weeks ago, I had the mail held and was given only a few pieces of mail at the post office when I returned. In the meantime, my friend wondered if I had gotten a gift card he had sent me. So I went back to the post office to see if they had any more mail for me--the clerk checked and said there was nothing.
I took another trip a couple of weeks later. When I went back to the post office, the clerk brought out the mail from the previous trip, including the piece with the gift card! I know it had to have been there a while because there were magazines dated a few weeks earlier.
Another time I picked up the mail and discovered mail for about 6 other people mixed in with mine.
The other day I picked up my mail. I was looking for a package from amazon.com, since I had received an email from them saying that the post office had tried to deliver it the week before, but there was no package in the pack of mail the clerk gave me. I told the clerk that I was expecting a box and he went back to check. While he was gone, I started looking through my mail and found the little yellow slip stating that there was a package for me. The clerk came back with nothing--I gave him the yellow slip and he went to get the package from the other side of the building.
I could go on, but....