I like the Kindle's original cover. Here's how I hold the Kindle when reading:
I'm right handed and I want my right hand free for such things as picking up my Diet Coke. To turn the page, I move my thumb over to the Next Page button:
-- and yes, I do press it with my knuckle and not the pad at the tip of my thumb.
When I first got my Kindle, it would occasionally slip out of the cover. I discovered that the little plastic tab wasn't securely glued into the slot in the suede, so I grabbed it with a pair of hemostats (fancy tweezer-like implements) and glued it in the right place with some Super Glue that my hubby keeps around. I pressed the edges of the slit in the suede tightly until the glue was setting up. Voila! No more problem with the Kindle sliding out. I can hold the whole thing up by the folded edge of the cover and the Kindle is held very securely in the cover.
I put the Kindle to sleep every time I'm setting it down and not intending to pick it up again. Since I had gotten into the habit of putting my laptop into stand-by mode every time I walk away from it, it was not difficult to transfer that action to the Kindle. If you leave the Whispernet antenna turned on, it's even more important to put the Kindle to sleep instead of waiting for it to time out and do that itself -- there's 10 minutes of network activity you've avoided and the battery charge will last that much longer.
I don't use MobiPocket Reader to synchronize and transfer books to the Kindle. I just allow Windows to mount the Kindle as an external hard drive and copy the files over that way. I also do my own backup of the books I've downloaded from Amazon by copying them to my laptop or to a USB hard drive.
I'd love for the Kindle to support some kind of foldering system -- and for that to be recognized by the Content Manager built into the device. I want to have the main/home menu display a limited set of the books on the Kindle such as the one I'm currently reading and samples I've downloaded. I'd like to have a folder that I can move a book to when I've finished reading it so I can easily see that it can be removed the next time I connect the Kindle to my laptop. But, I'm managing without such a file system.