Lufthansa is offering a limited number of low fares for travel within Germany and Europe. There does not seem to be an end date to the promotion. I tried several dates for several itineraries and was finding low fares associated with this offer throughout most of 2013.
The fare sale is broken up into to segments. Fares for travel within Germany or those that have direct flights start from €99. For itineraries that involve connecting flights in either direction, those fares start at €159.
Other requirements of the fares are as follows:
Travel within Germany: A 1 night stay is required (any day).
Travel to European destinations: A Saturday night stay is required.
Maximum stay of 3 months is required
Non-Refundable / Non-Changeable