I'd just give the answer, but that's no fun

https://blog.adafruit.com/2026/10/28/the-oldest-gui-application-that-still-runs-on-windows-11/

I happen to keep .exes in dated folders and copy them forward to install on a new laptop. There are others in my archive, but these are the ones I currently use.

1999-UltraEdit v6
2004-LView Pro 21
2005-MagicFileRenamer
2007-Sketchup (but now use the still-popular free, local version 2013 Version 8 )
2008-SimpleFamilyTree
2009-FreeCalc
2010-FaststoneCapture

Picasa photo manager is the only one I still do that with.

I used to keep a big collection of installers, but there just aren't that many apps I'm wedded to now.