I recently finished up an essay examining the Girl Scouts, their cookies, and their finances with reference to whether they are inefficient or corrupt.
What is the relevance to LW? (The essay is aimed at a general audience & assumes no knowledge of LW material, though it links heavily to LW in justifying why one should make predictions - such as about Girl Scout finances - before looking at data.)
Well, on occasion, people ask questions about SIAI that they could have answered by themselves, such as by looking through SIAI financial filings. This kind of annoys me. This essay serves as a demonstration how one could investigate a charity on one's own, without simply trusting GiveWell's recommendations (good though they surely are).
Reading SIAI's filings may be a future essay; until then, it is left as an exercise for the reader... (EDIT: One such reading is BrandonReinhart's extremely thorough SIAI Fundraising Article; highly recommended.)