Hi,
I did not check the prepaid cost for voice and data usage for traditional prepaid cards, but in general those costs are elevated and data traffic is generally no feasible option. F.i. the Lebara card would be an option, easy to access and low cost as to voice, but data does not seem to be part of the package. Typical users are expected to be non-professionals, I think.
If you can get your friend(s) to establish a contract with f.i. Bibob (
www.bibob.dk), though, I think this would be the optimal solution. You have to have a Danish CPR (personal) number and a Danish address, though, so your friend has to make the contract in his name. It is an open ended contract, you can terminate it after 1 month (I think), no monthly fee, calls to Danish nos (fixed or mobile) 8 Euro-cent/min, no set-up fee, SMS 1 ct, data 26 ct/MB, starting-up package 20 EUR fully refunded, calls to foreign countries rather expensive. But best would be their data flat rate, for the first month only 6,50 EUR with an allowance of 1000 MB free, the 2nd month will cost 17 EUR, though. GPRS and UMTS up to 512 kbits/s max. via the 3 network. International calls could then be done via voip.
Probably Bibob will accept your foreign c-card. But the CPR-no will be indispensable, similar to the Italian codice fiscale. Only that in Denmark the CPR-no actually is the key to any physical existance. So I think you will better ask for a helping hand from your friends.
Please revert if there are further questions.
Kind regards,
hkunse