The best offer currently available is what I, and thousands of other techno-freaks in Greece, currently use and there is no other service like that offered by any other provider.
It's called WIND Plus non-stop. It is a service that gives you unlimited WAP access with 3,49 Euro per month. It is marketed as a service that offers you unlimited access to the WIND Plus portal but it actually allows you to surf the whole internet unlimited. This can be done using your phone's browser, Opera mini or even by tethering your phone to a computer and using the settings that I'm copying below.
Moreover, WIND also allows you to access the internet with the same settings even without the Plus non-stop option. In that case they will charge you a WAP access ticket of 42 cents, every time you initiate a GPRS session (maximum session time 24 hours, i.e. you can keep the session open for an entire day and be charged one "access ticket", after the first 24 hours, the session won't be interrupted but a second ticket will be charged and so on).
The WIND plus non-stop option with 3,49 Euro per month is the best choice and the WIND plus pay-per-access scheme is also good if you're planning to stay for less than 9 days and willing to keep your WAP session up and uninterrupted whole day long!
In order to activate WIND plus non-stop on a WIND prepaid you have to SMS the word "PLUS" to 349 and the service will be activated for the next 30 days, after which you have to send this SMS again. In order to activate the service 3,49 Euro will be deducted from the prepaid balance of the account. For contract (postpaid) subscribers the WIND plus non-stop option is activated at WIND stores.
Nothing more whatsoever is charged for data usage on your account after that, provided that you're always using the WIND Plus access point (gwap.b-online.gr)!
The WIND plus settings can be automatically downloaded from
www.wind.com.gr to your phone (make sure you're always using the WIND plus profile and NOT the WIND Internet one which charges by kb, many users actually delete the WIND Internet profile from their phones to avoid accidental charges).
In order to use the WIND plus service with a computer tethered to your mobile phone, you have to enter the following settings to your computer:
access point "gwap.b-online.gr", username "wap", password "wap" for your cellphone's PC suite and you also have to set the following proxy server on your web browser IP: 192.168.200.10 port: 9401 as well as on the windows connections panel (for IE and MSN Messenger).
I have used that with a Nokia N70 tethered to my PC through Bluetooth and USB and the Nokia PC Suite and it worked perfectly. Under 3G coverage it had speeds up to 200-250 kbps! It worked excellent for browsing, emails and MSN Messenger for me!
If you pay your account (for prepaid subscribers) with a WIND Bonus American Express card the WIND Plus non-stop service is offered free of charge, also the service is offered free of charge on the WIND MAX postpaid plan (for all users regardless of account payment method).
There is also the WIND 1 postpaid plan which has no monthly fee and no commitments. It has the same charges as prepaid but it is postpaid. I don't think it would interest you, it's just an interesting option for people staying longer in Greece but not long enough in order to sign-up for a "real" postpaid plan but are also too lazy to buy prepaid vouchers. On WIND 1 (unless you're paying using WIND Bonus AM.EX.) you have to pay 3,49Euro per month for WIND Plus non-stop.
There is one drawback to the service though, which is not such a big problem for everyday internet usage:
No single entity above 1MB in size is allowed for download. This means that you can surf the web, check your emails (but not download attachments larger than 1MB in size) and chat on MSN Messenger through WIND plus but you cannot download files that are larger than 1MB as these will be blocked by the above mentioned proxy server. Using WIND Plus on my laptop for almost a month when I was away from a fixed ADSL connection I have to admit that the 1MB file size limitation has never been a problem!
In this case and if a file download is absolutely necessary, you can still use the WIND-Internet profile "gint.b-online.gr" which charges per kilobyte (the charge is about 0,0014 Euro per kilobyte). I used that to download the online upgrade for my phone's software which was 2MB in size, it cost me about 3 Euro...
Visit
www.wind.com.gr (where you can also request for automatic settings to be SMSed to your mobile) and
www.windplus.gr where more information is available regarding mainly the WIND Plus portal but also the WIND plus non-stop option for unlimited WAP access. You can also check whether 3G coverage is available in the area you're visiting (some islands are covered too!)
If you're looking for a WIND prepaid SIM (in case you don't have one already) these are widely available with 5 Euros at virtually any kiosk around Greece and at WIND stores. The prepaid card gives you 1 Euro credit on activation plus 1 Euro credit per month for the next 4 months provided that you recharge your account balance at least once during the month. This means that if you recharge your account at least once a month (cheapest WIND recharge voucher available is 3 Euro) you will get 5 Euro of credit back in five months (matching the initial cost of the prepaid package)!