Ipad APPS - which one DO I NEED?

I was reading the post by Debbie Lynn TO Ipad or NOT to Ipad  and I got to thinking....

I have an iPad - hubby bought me the 32G for my birthday, yes I will never ever fill up the memory.

That was 3 months ago and I know I'm still not using it to it's fullest capacity.

I do know I've read more books in the past 3 months than the past 3 years.  I always have a book with me, since Kindle is loaded as an app.

I have games, Skpe, Dropbox, etc... but what can I do on my IPAD that makes it indespensible?  

I know that there are those of you out there that can help me.

So all you IPad users, those of you that REALLY REALLY USE your IPAD as a MUST have I don't know what I did without it, I want to hear it.

What Apps do you have?

How do you use your IPad for productivity?

Let me have it.  I really want to know, what can I do with this little computer that is almost a large cell phone?