The Mathematica I know (v5, v6) were usable completely offline. Can one use the recent Mathematica version in an offline mode? How many parts are really part of

The Mathematica I know (v5, v6) were usable completely offline. Can one use the recent Mathematica version in an offline mode? How many parts are really part of the online service? I guess the WolframAlpha style data sources (country, city, etc. db sources).