The impossibly cache?

While I won't say its impossible, one has to wonder what is the best container?
Is it something that can or can't be found?
While 2 of the 3 caches I've hidden thus far under this account are pretty easy, my last placement took some time and its very tough.
TOUGH? Yup, it took planning, wasn't something I jumped into and I actually researched this idea first. I found no cache like it and figured that it would have to be done.
So, over the course of a week, I slowly finished it off.

NO, I can't tell you. If I told you, you or others could and would find it.
The hints on the site page are enough to find it. The math problem will lead you to withing a few feet of it, and actually you can see it from that point.
I'm not going to say much other then the next cache I place will be tough, but nothing as tough as this one. I have the feeling that too many tough caches might just lead to other cachers not looking. OR WOULD IT?

I've not posed that question yet to anyone. Do you like a tough or HARD TO FIND cache? I'm guessing from the reaction that MeanStreak got, people from beginners to veterans love it.

So what cache am I rambling on about?
http://www.geocaching.com/seek/cache_details.aspx?guid=33c2dc67-4a96-4f9a-9bae-aef844b87864
or
GC1DGZA

So go look and perhaps you can take a crack at it.