Yup - on my hard drive. Of course I can't throw any out. Actually, I am slowly working through them, tossing some duplicates, but this must be a packrat disorder.
The solution may be to get another outboard drive and move it all there... where it can be joined by many many more since memory is so cheap!
In the attic we have a LARGE box of picture prints (remember those?) which we never look at - and I have videos over 20 years old I have shot and never watched.
It must be something about wanting to preserve life's moments.