Comment aldi? (Score 2, Informative) 153
http://www.billiger-telefonieren.de/aldi-surfstick-flatrate-webstick/
Sorry, link is in german, maybe babelfish will help out.
I have the austrian "hofer" equivalent, which is a pure data prepaid. It seems to work slightly differently in germany, where it's an addition to a prepaid voice sim. I'd acctually prefer the german style, but oh well.
I'd recommend combining it with a S60(or Maemo) Joikuspot compatible handset, that way you can use the voice part as well.