There is a good amount of high-quality research material provided by CLARIN-D and its centres. Below, please find a selection of popular resources, each of which has its own user/search interface:
GermaNet is a machine-readable lexical-semantic network for German, maintained by the University of Tübingen. Part of it is also integrated in EuroWordNet, which is an integration of the word nets of various European languages via an interlingual index.
The German reference corpus DeReKo is an electronic archive of text corpora of written German. It was originally created in 1964 and is maintained and extended by the CLARIN-D centre IDS Mannheim (Institut für Deutsche Sprache). Currently, it consists of more than 25 billion running words and is the largest collection of electronically available contemporary German. DeReKo is publicly available through the web application COSMAS II.
The German text archive DTA is a scholarly text archive maintained at the CLARIN-D centre Berlin-Brandenburg Academy of Sciences. Originally funded in July 2007 by the German Research Foundation (DFG), the goal of the DTA is to provide German texts from the period between 1500 and 1900 based on original publications. These are digitised and published on the Internet as a linguistically annotated full text corpus. The corpus consists of different genres and disciplines.
The resource "Deutsche Wortschatz" is a database consisting of 35 million sentences and 500 million running words. It is based on 9 million different words and word groups and is located at the University of Leipzig.
The digital dictionary of contemporary German, DWDS, provides information about contemporary and historical German words. It consists of 465,000 lexicographically examined entries, different text corpora and statistics derived from them. The dictionaries are partially extended and updated at the Language Centre of the Humboldt University of Berlin.