This is a thread for recommending stories you like, especially those that haven't been posted in this section (though if you like one of those, go ahead and rec!). There's a lot of good stuff at AO3, tumblr, and ff.net that doesn't get discussed much here.
To start with, Fraternite by Roberta Wickham is one of the best fics I've read in this fandom and hands down the best Amis one. It feels like all the best of the accumulated years of fanon, meta, and research combined with fresh ideas, smooth prose, inspiration from the little details of canon, and lots of well-done emotional moments. There's at least one chapter still to come. The highlights of this for me include the friendship between Enjolras and Combeferre, as well Courfeyrac's gallant introduction and the well-thought out plotline around a possible traitor.
From the ongoing Les Mis Across History AU-fest on tumblr, a particularly interesting fic out of the bunch was ratheralark's WW1 AU, which probably appealed to me because I've been reading a lot recently about the debates among socialists about whether or not to support the war, a bitter division that contributed to the ultimate split between Socialists and Communists. This fic dives right into that subject matter, having Marius and the Amis argue it out. Things I liked about the execution: giving the disagreement between Marius and the Amis, and between the Amis themselves complexity and more than one or even two sides, and reworking a canonical scene beautifully without merely repeating it.