Even though the iPhone 5 is quickly becoming the iPhone of choice these days, there are still plenty of good cases for the iPhone 4 and 4S -- including those with keyboards. The Boxwave Keyboard Buddy Case has been out for nearly a couple of years, and they've added a $79.99 (on sale from $89.99) version that includes a backlit keyboard for use in low-lit areas. I tried it on my 4S for a couple of days, and while it's a solid case, it's not one I'd use unless I absolutely need to have a keyboard.
Design
The case is made of molded plastic and is quite a bit thicker than the normal