The template of these letters is always the same: a black background in the shape of a square upon which is typed, in caps-lock white font, a short letter written to a famous person who has died. The length of the letters vary (the shortest one, addressed to J.R.R. Tolkien, reads simply: "GEEK"). The letters are by turn serious, funny, or inspiring, but each of them captures, in the most concise way possible, a certain aspect of each dead person's life or legacy.
This is Celine Song's letter to Sylvia Plath, which can also be found here at her website: