I'm making a new skin for VB and decided to go with a fixed width of 1280 instead of 1600. The old foot and header were 1600px wide. I decided to forgo the footer but it kept tossing up the image.
I knew I had changed the name of the image file and dumped the url so it couldn't find it. But it came up over and over. I must have read every template at least 3 times looking for another link I must have put in and didn't remember doing it.
It finally dawned on me that I had set the cache to hold an image of the forum for 3 days. It had just reset the cache and was holding the image. So I forced a dump of the cache and tada, it was gone.
Time spent: 2 1/2 hours.
Yeah, I can relate to that... (BTW Big Red turned out pretty nice as a result. I made a lot of adjustments while looking for that gremlin.)