I will start with mine:

Amazon Kindle 3G


-The screen is just right. Great for reading, as there is no glare, unlike the ipad or the sumsung galaxy tubs.
-Its pretty light and fits in my palm, so i can carry it anywhere
-works with most known formats of ebooks, but it specializes in mobi pocket format. That is one of its disadvantages, as all the other ereaders support the epub format, which is which most libraries use
-Battery lasts a life-time(10 days without 3g or wireless).
-it has FREE 3g....thats right free!!!

One big problem is its browser. The browser is sluggish, and what makes it worse, is the fact that there is no touch screen, or a button that helps in proper navigation.