I just finished Donald Knuth's "Literate programming" book and in there is one of the most wonderful papers I've read: "The errors of TeX". The version in the

I just finished Donald Knuth's "Literate programming" book and in there is one of the most wonderful papers I've read: "The errors of TeX". The version in the book goes up to 1991 but on ctan you should be able to find "errorlog.tex" if you want to read the updated (I think the last one is from this year) paper. Knuth has documented every bug and feature fix in TeX since its first version and categorised it into categories A-T.