Pros: everyone who has a iphone 3g thats uses
-ipod music player
-ipod video/ movie player
-sms
-phone calls
-email (push)
-bright screen contrast
-facebook
-applications (of all sorts)
will tell you their battery will last ..sometimes just hours lol! maybe half a day ... so i tell you what friends, this is the best and cheapest solution

Cons: i wish it was cheaper, but at the same time i know it shouldnt/ cant be lol!
ummm its cool, it obviously doesnt look like a $100 piece of equipment, but it probably works exactly the same id say from my experience

Other Thoughts: i let my phone die today to 0% (auto shut down)
then i clicked this fully charged spare battery on the bottom.. charged for 45mins (?) and my bar has gone to about 60% approx.
so how much juice does this give? enough o finish whatever you were doing and get home to ur charger i guess

Bottomline: bottomline.
u know u need POWER
what is a iphone without being able to do whatever you need to do at any time (without having to worry about power all the time)
i tell u what, its not a very good phone.
so u dont need to tone everything down (contrast, data push etc) to "save battery"
u can experience FULL IPHONE 24/7 LOL
i hope this long as review was over 500 thanks

Pros: Designed for all iPod's and iPhone's. It works great, and it's very handy if you make a lot of trips like me. It has a nice Led indication and charges quick. It's very light and compact. You can charge you're iPod/iPhone and the battery in one time.

Cons: It has a bit of a leeway with the dataport of the iPhone/iPod. Led's are a bit bright :P. I also have a small problem with watching episodes on my iPod, because it's a bit fragile when you let the iPod lean on the charger.
On the iPhone and iPod classic the headphone jack is upper. But remind you can't listen and charge with a iPod touch or nano.

Other Thoughts: Maybe you can add an USB female port for charging through the USB cable, then it has some space for the headphone jack. (If you have a iPod touch or nano I recommend sku.04505)

Bottomline: Great buy and works like it says!

Pros: It works as it should:
- When plugged to the iPhone, the phone charges, draining the external battery. I find this useful because you don't have to carry this brick connected to your phone all day. Just plug it for about one hour, and you got all the extra energy you needed.
Also, has a bypass port so in the end you can connect your computer to the battery, and the bat to the iPhone. And they both will charge, and the phone will be able to communicate with iTunes.

Cons: made of plastic, the design is a bit fleaky, although has cool red and blue lights ;)
When plugged to my (not-3G) iPhone, it doesn't perfectly fit it. On the other hand, this allows me to connect without removing my iPhone plastic case; so maybe this is a Pro instead :)

Other Thoughts:

Bottomline: If you often spend one night out and run out of battery in the worst moment, then definitely this product is worth spending some $ and letting it into your backpack.
Nice product.