If you don't know what we are talking about, don't post here!
Then again, having 2 monitors can help with that significantly I could use 3 tho :/
I have 2 as well, 1 horizontal, 1 vertical. And right there with you on wanting the third.
I don't think that it is very good idea to compare computer desktop and physical desktop... can't comfortably put something on top of mess you have on your physical desktop
Is this not similar for a messy computer desktop?
- Grouped icons (say for different projects) start blending together once too many appear. So, you might have to now resort and order them.
- Fear any monitor resize (say an old msdos program that wnts to force a windows resize on load) as that could rearrange your beautifully set icons... into a disaster if you have a lot.
- Oppps, ever then rearrange your new icons just as you want after windows messed it up, only to have your pc crash and back to the beginning we go.
- And how about dragging and dropping something on the wrong desktop spot (maybe wasn't even meant for desktop but computer decided to "freeze" for a second and it drops). Damn, all those icons that were in place just got jumbled, again.
I'm sure I'm not the only one that has encountered these terrible time wasting moments with desktop icons. Point being, it's a bit more than just a weird fetish.

With Circle Dock... F1 and my links are popped right at my mouse pointer (no need minimize windows to view my desktop to find what I need), F1 again and their gone. Never messed up... easily added to... with browsing functions built right into it.