Dynamic Generic Data Transfer Object

This has to already exist, but I just can't find it, or don't understand what I am looking at.

Simplely put I want to do this.  I want to have an object that I can use that would be generic, but dynamic at the same time.

The code snippet shows something like what I want to do.  I want to create an object, tell it why datatypes I am going to use along with the names of the properties I want, and then be able to fill out the object with the values I want.  So I can pass it along through the application.

So how would I create this generic DTO?

GenDTO bob = new GenDTO();

bob.add(datetime "StartDate");
bob.add(string "Name");

bob.StartDate = '1/1/2010';
bob.Name = 'Smith';

GenDTO g123 = new GenDTO();
g123.add(int "ID");
g123.add(bool "Terminated");

g123.ID = 2;
g123.Terminated = true;