In my case it's either friend or AA... so one of these would be great :)

I have jumper leads in my car, and have used them a few times, more often to jump the wife's car than mine. If there's no friendly person around to jump from, I have State Roadside Rescue. I've used them a couple of times, but not for batteries - once for a broken cam-belt ($4K later the car was good as new, replace your cam-belts as soon as recommended, don't wait a month and drive over the Mamakus on Easter Sunday) and once for a stuffed starter motor.

We have so many flat batteries - on everything, all the time - we've hard wired a set of 25' cables into one of our utes. Twin battery so can choose a 12 or 24V boost.

Also carry jumpers in our car tool sets, and have an AA membership.

I will call friend. 

"A friend in need is friend indeed." 

As I found out last week if my car battery is flat my wife calls her husband. This would save me some phone calls :)

I'm keen! We have jumper leads and also AA, but often something like this is useful when camping with the kids.

I rely on the AA.

Had a recent experience when our car with ~6 year old battery was left for a week without being used. After a few failed starting attempts when the starter motor was pretty sluggish, I managed to get it started. Got the battery checked and sure enough, it was almost dead. Replaced the battery and all was fine.

A few days later parked the car at Auckland airport for 2 weeks and returned to find the battery was flat - the inside light got left on! I called AA who said that the airport car parks actually have battery packs but they would send someone out. Managed to track down the car park guys (arrived at the same time as the AA) and they started it promptly. They both left promptly and I was all set to but turned on the headlights and the engine died. Had to call the AA back again and he was attending to someone else with the same problem at a different airport carpark. A bit of a bummer after coming back from holiday and flying through customs/baggage claim etc.

One of these devices would be great for the next time

I would call number one son..payback for all those days and nights driving him to and from everywhere before he got his own car, then AA. I have one of those other big jump starters in the boot but it always goes flat between uses. It's a bit like carrying around a flat spare tyre, no good when you need it

This is topical to me - this morning I went to leave home early to replace car battery that was taking longer & longer to crank over, to be met by ....nothing!  The car battery was so flat it didn't even have enough juice to wind over the starter motor.  Guess I shouldn't complain because the battery was about ten years old going off the manufacturer date stamp.

Had to call state roadside rescue to give me a jumpstart, then straight to auto shop to buy a new battery.  Father in law has one of those jumper packs mentioned in earlier posts and I was tempted to call him, but figured I might as well get money's worth from insurance co!

Thanks for the chance to win

I'm an Aussie now living in NZ so, after the shambles that masqueraded as a Wallabies team the other night, I am unable to face having to ask a kiwi for help if I should happen to have a flat battery.  Oh, I know they'd help but the price I would pay in terms of "helpful" suggestions about the Wallabies would be enormous.  I need this.  First use would be to jumpstart some heart into the Wallabies

The last time the car battery was in the airport parking lot. Someone had left the lights on. Not laying any blame. Just sayin'. Anyway, we were calling the AA but it turns out that the airport has a portable car battery charger! I'm guessing this happens quite a bit. Anyway the young guy was able to get the car going and everyone got home safely with no fuss & no need for the AA that time. Anywhere other than the airport we'd be calling the AA.

So, for other folks, if you find yourself stuck see if the car park owner has a portable battery charger. It's worth asking, especially if you're stuck at an airport.

If I won this I'd be very stuck whether to gift it to my SO or to my Dad. On the other hand I might keep an eye out to see how much they cost and get two. It would save my Mum worry when my Dad's gone tramping. His phone battery never lasts the week he's gone, even when the phone is off, or at least, that's the story he gives her...

This is probably my current solution to flat car battery:

Although this can also go flat, it takes nothing more than a couple simple pumps to "charge". I wish our car was as usually friendly.

With an automatic car it is no use push starting and until recently I have used jumper leads but have been told that you can fry your on-board computer, so I have put those in the bin.

I have also called the AA for a non-starter before, but they can take ages to arrive.

So you can see that one of these gizmos would really save the day.