Okay, I think I found the culprit. I found an executable called StockViewerControlPanel.exe in the directory of Microsoft Application Compatibility Toolkit, which I had installed a few days earlier. Apparently it's some kind of a "demo application" bundled with the toolkit..
The full path of the file:
C:\Program Files\Microsoft Application Compatibility Toolkit\Compatibility Administrator (32-bit)\Demo Application\StockViewer