VirtualPet.net - The Virtual Pet Network!
Could be anything from an 'Adult' site (Does penthouse offer virtual 'Penthouse Pets' yet?) to a childrens site where they take care of virtual animals like dogs, cats, lizards and the like (but not Penthouse Pets).
On top of being a highly searched for descriptive term, To me the 'pet.net' part has alot to do with what really makes this an exceptional .net imo! It is so easy to say and read (note how easy the lowercase version reads because of the lp tailing off in differet directions, look - virtualpet.net). Additionally, Everybody can spell and type it and even a peabrain could remember it. That all adds up to virtualpet.net working well in cross-media promotions.
Personally, I wouldn't sell it for any less than $7,500 usd. I would either develop it someway as mentioned above or just lock it up until I found a sponsor or buyer that would meet my price for it. If I was proactively target marketing it to sell it, I would start with companies participating in Microsoft's .NET project.
On top of all that, it just has a sort of mysterious excitement about it that draws one in I think.
Please let us know what you end up doing with virtualpet.net. It's a .net that makes sense.