Notepad is a note taking tool for Kindle. It only costs 99 cents, and it's worth much more than a buck.
Why is Notepad so good?
It's fast. It's roomy. It's great when you're reading in your e-reader and you want to note something - whether it's from the book, or whether it's got nothing to do with the text you're reading.
Here's an example. It's long past midnight. I'm reading along in Grisham, and suddenly the thought pops up that I need to check that FedEx delivery: did it arrive? When was the deadline again?
Of course, Notepad is just as ready for you to jot down items for the grocery list or your calendar (anniversary, birthday) as it is something work-related.
Why is this better than the notepad in your nightstand drawer?
Notepad via Kindle allows you to take these notes and put them on your computer (and vice versa). Plus, if you don't have that pad and paper next to the bed, Notepad means you don't have to get up and search for stuff.
It's proven to be handy for me in my writing and I think you might find Notepad useful, too.