For the 800th anniversary of Maimonides’ death, JNUL has made a collection of manuscripts available on-line.
Today is the 800th anniversary, in the sense that it has been precisely 800 solar years since the sad event, which occurred on December 13, 1204. You may object that today is in fact the 20th, and you’d be right. But when looking at a date from before 1582, one must always consider the possibility that it is a Julian date and not a Gregorian one. The Julian calendar had drifted 7 days by 1204; I’ve corrected for the drift.
How did I know the date was Julian? I checked it against the Hebrew date of his death, 20 Tevet 4965. You can do the same thing at this handy calendar site. This year the 20th of Tevet will fall on January 1st.