Learn the most vital modifers:
manifesto filetype:pdf sputnik site:dk
A more thorough list is here: Google Operator Reference
The builtin calculator knows the current currency:
And a number of different units:
Google Scholar Search scientific literature and articles.
Google also indexes executable files, as a search for "Signature: 00004550" reveals.
Inktomi is a competitive search technology.
It is licensed and used various places, most notably it is the basis for Yahoo‘s web search.
It has a couple of advanced features that Google misses, such as the ability to search for pages which links to a file with a given extension. (Consider the scenario where you are searching for pages with a molecule structure file - a *.mol2 file - with structural data on the HIV1 protease - this can be accomplished using Yahoo Search like this.)
The search syntax is described in details here: Inktomi search syntax