I have a similar one for my PSP as well, and it's great.
I have this. It holds the Vita, 2 memory cards, and 8 games securely. It is a bit bulky, but it does the job. I had my PSVita on the center console in our van and when accelerating up a hill I heard a load bang. I then noticed my PSVita wasn't on the console. After I got to my destination, I realized it had hit my metal tool box. There was a little ding on the hard case, but the Vita was secure, no visible damage and haven't had any problems playing it. That happened about 4-5 months ago.
Oh and you can make your own insert image for it, to make it more unique if you'd like.
Here's someone's review on youtube, so you can get a better look at it.
They're $15 on Gamestop right now. There are other buyer reviews there. Average 9.8 as of this writing.
I am using the plastation brand hard case. Got it at best buy. The vita fits in it with no movement and I have not done it but it seems good enough that if you would drop it your vita would not get hurt.Take it to work every day in this case.So far so good.
I also recommend the PlayStation Vita Custom Crystal Case. Very durable yet light and you can carry lots of stuff on it and for me its very cool that you can customize its look.
More info here
Pick34 that is the one I was talking about. You can get it at best buy. I think you could throw it across the back yard and it would be ok. But I probably would not try it.
This is not really a case, it's a hard cover. I have it, and I've gotten different cases and always go back to this. You just flip it open and play, when you are done you just snap it shut and it feels like it's well protected. It is also very slim and still fits in my pocket, and it even looks pretty sweet.
As you can see, the reviews speak for themselves. Cheap, too. The only downside is that it doesn't store any games or anything, but if it did, it probably wouldn't fit in my pocket. So I just use a small game case and put that in my other pocket.
Edit: Oh, I forgot another cool advantage. You can flip the top cover over the back and sort of use it to stand the Vita up if you want to watch something on it. It might not work well on a slick surface, but on fabric of some kind or carpet or a mousepad or something it works great.