Several years ago, my father started collecting a very specific kind of Victorinox Swiss Army knives.
He collects the Classic version of these knives.

No other versions are acceptable.

It needs to have the blade, nail file, scissors, key ring, toothpick, and tweezers.
There are imposter types that have bottle openers instead of scissors, pens instead of tweezers,
or LED lights.  All of these non-Classic types are not allowed in the collection.

He is very strict about excluding these non conforming knives and they must be kept elsewhere.

When he started collecting, he stated he was never going to go overboard with buying
the knives.  Let's see where he stands.

Here is one of the display cases.
Yes, there are sixty-five knives in that one display case.

Keep in mind that is only one of the SEVEN full cases he has of knives.
In case you are slow with the math, those cases hold
four-hundred and fifty-five (455) knives.

That is one hell of a lot of knives.

But we aren't done yet.

On another counter, he has an even larger cases that holds more knives.
The large case holds about one hundred and sixteen (116) knives.

That makes a total of 571 knives.
 

There are NO DUPLICATES. 
Duplicates are not allowed in the collection

There is no sign that he is slowing down on his collection.
For Father's Day, my mother (the enabler) gave him four more empty
cases capable of holding three hundred and sixty-two (362) more knives.

His current eBay feedback rating is 255, almost exclusively from knife purchases.
On eBay, he has a nemesis that tries to outbid him on knifes.  Dad takes great joy in
beating his rival in the auctions.  Price is no object when it's a knife he does not have.
To think there is another man out there with hundreds of these knives out there boggles
the mind.  I should form a support group for Sons of Victorinox Swiss Army Classic Knife Addicts.

I intend to expand this page as I get more details as the extent of my father's madness.

So if anyone wonders where my eccentricity comes from, I think it's clearly genetic.

When my Dad hits 1000 knives, I'm throwing a party...