One thing I really love about languages such as Python is that if you have a piece of code you'd like to try out, you can just open the interactive shell and do it in seconds.

Is there a Visual Studio add-in that does the same for C#?

Basically what I'm looking for is something that opens up a window or tab with a text editor (preferably with code completion, because VS does it so nicely) and a button that runs the code and displays the output. Extra points for convenience features such as displaying complex output in a user-friendly way (think Firebug's console.log), automatically referencing all the assemblies the current project references, etc.

I tried googling for a while, but either I fail at coming up with good keywords, or no-one has made an add-in like this. If there really is none, I'm considering making one myself.