I would say to precompute anything the user could run to make things run faster, however accurate anticipation of user needs is really hard. I only thought of

I would say to precompute anything the user could run to make things run faster, however accurate anticipation of user needs is really hard. I only thought of these tasks: In a word processing: we can load grammar and nlp engines and download and analyze trends in web text for improve suggestions in nearly real time, also trying to understand what the user is writing and aiding to improve not only orthography and grammar but style too, for example. In Web search, personalizing the whole searching and browsing experience downloading and processing partial results and with intelligent assistants running in the background (this is my favorite).