PAYG mobile contract with 1c/min to 08 numbers - Germany

When I was in Germany in August/September, I saw big adverts in the signs of some phone shop windows for a pay as you go sim with calls to 08 numbers for only 1c/min. I'm interested in this as I figure the international phone cards you can buy (100 mins to somewhere for 5€ etc) mostly require a call to an 08 number to use them. Unfortunately I have completely forgotten which company was advertising this, and since I've arrived in Berlin I haven't seen a single advert for it. I'm aware that the offer may no longer exist, but it might also just be that the advertising campaign is over.

Any info would be useful! Thanks

What is an "08" number?

Like 0800 free numbers, which I believe is what the phone cards use. I haven't seen them in the shops here, but you can buy them over the internet and the email you the code.

Also maybe it covers some kind of corporate numbers like calling your bank and that kind of thing. Must be something useful since the advertising signs were so big!

There is no charge for 0800 numbers from mobile phones anyway, so long as the 0800 number owner has permitted access from mobile services, you are not roaming, and the call in in-country - not 0800 owners permit calls to their services from mobiles as they have to pay for the call and such calls from mobiles are more expensive, but usually then you simply cannot call the number anyway.

ok thanks. useful info. In the UK a call to 08 would cost 10-40p/min, depending on provider. But if 0800 calls are free, what was this 1c deal for then??