Fonic, a discounter on the German O2 network, will offer a prepaid dayflat for € 2.50 per day starting on September, 15th.
HSDPA with up tp 3.6 MBit/s can be used, where available.
VoIP and filesharing will be blocked.
There won't be any traffic limit, however bandwidth will be reduced to GPRS-speeds, if 1 GB per day is exceeded.
The dayflat will be valid from 0 a.m. until 11:59 p.m. - so billing works by calendar day.
Existing customers must contact customer care to change the data tariff from the current volume-based tariff to the new dayflat.
New customers, will get 5 free days of internet access when registering between September 15th and 30th. Later a single free day will be granted to new customers.
Also a bundle of a 3G-USB stick and SIM card will be sold for € 89,95 (incl. shipping) from September, 15th:
http://www.fonic.de/html/surfstick.html
Fonic SIMs and vouchers are sold at Lidl, DM and Real supermarkets.
All in all this is a great offer underbidding current dayflat offers of T-Mobile and Vodafone by 50%.