Good morning,

just read an article talking about the TUIfly all you can fly ticket.

Basically it competes with the Deutsche Bahn Interrail ticket. Bookable 14 August thru end of August. Travel between then and end of October. All taxes and fees inclueded in the €199.

So far I could only find a German article, sorry
http://www.welt.de/wirtschaft/article1093798/TUI_fuehrt_Flug-Flatrate_fuer_junge_Leute_ein.html

You need to be pretty flexible.

Use babelfish.altavista.com to translate it easily.

ticket is now bookable until end of August.