I'm risking to get violent down-votes to this answer, but the truth is more important. I'll try to argument. The answer is: no, there is no such thing.
Most of my arguments can be found in my comment to Solution 1, but that's not all.
Is there a base class/object? No. These are actually two different questions. There is no such thing as base class, because there are no classes, and nothing fully analogous to OOP classes. And there is no such thing as "base object" because there is no such thing as inheritance for JavaScript objects.
Don't get me wrong. With JavaScript, people do create some hierarchies. But those hierarchies are not something intrinsic like in .NET. JavaScript works in very, very different ways. The hierarchies based on prototypes and/or constructors are only functionally similar to class hierarchies, but are totally different in nature. More importantly, the concept of "type" is so different, that it would be wrong to consider the concept of JavaScript "type" as a type of a strongly-typed language. You can understand what a type is from, say, this description:
typeof — JavaScript | MDN[
^],
JavaScript data types and data structures — JavaScript | MDN[
^].
If .NET, things are fundamentally different. Even the primitive types, such as character or integer, are derived from
System.Object
. But they are derived in a twisted way, through
boxing. This is a whole big separate topic. There is nothing like that in JavaScript, not even close. But it's more important to understand that even the "object" types have no predefined "inherit", "derived" or "is the base of" relationships. Not even close.
Perhaps most important things you have to understand about JavaScripts are: 1) JavaScript is the world's most misunderstood language; 2) you should not be distracted by seeming similarities between OOP and JavaScript. Please see:
JavaScript: The World's Most Misunderstood Programming Language[
^],
The World's Most Misunderstood Programming Language by Douglas Crockford[
^],
JS Objects: Distractions[
^].
—SA