This case selected by Kat: Sidney Edward Johnston, missing since January 22, 1990 from Davenport, Iowa.
There are strange circumstances involved here, and possible evidence of a struggle at his house, including holes punched in the wall. However, I’m not sure if the holes happened around the time he disappeared, because the casefile mentions him having screaming arguments with two acquaintances at his house in the months before he vanished. (For what it’s worth, both of these people passed polygraphs.)
Johnston, always a frugal man and a loner, had been having financial problems and got into legal trouble before he vanished, and he asked his brother for money. At the same time, though, he uncharacteristically gave away $30k. It’s all very strange.
I haven’t updated his case since I added it to Charley in November 2010. Sidney would be 71 if he’s still alive today, which I suppose he could be. His car did disappear with him and was never located.
Iowa Cold Cases has a detailed file for him. A commenter suggests that the changes in Johnston’s behavior before his disappearance could have been caused by a brain aneurysm. I doubt we’ll ever know.