Once upon a time long before I was a domainer, I kinda owned
-.com (Dash dot Com) for at least a few hours!
Turns out it made it through some loopholes in the registrar platform (must have been NetSol or TuCows at that time) .. but ultimately it got buggered up because domains can't start or end with a dash. Needless to say I was heartbroken when we figured it out!
In a way I guess it truly was the only "priceless" domain to ever "kinda" exist! lol
Mind you I'm pretty sure that was after verisign blocked all but grandfathered L.com and LL.com .. so likely would not have gotten it a second time had the first passed! lol
ADDED: Actually that was before Verisign I think .. but I think it's an Icann run for the dashes and possibly the stipping of 1 and 2 non-grandfathered character domains. Or maybe it was a NetSol thing .. anyhow .. whatever it was .. I had -.com sitting in my account for a few hours at least .. lol.