I am in awe of the good folks at hebrewbooks.org. They recently added 683 more books bringing the grand total to close to 47,000 Seforim, all freely available online for learning and/or download.
What is most gratifying, is that recently there has been a major shift by HB, in that they are adding many of the contemporary Seforim to their database. This is a huge money saver, as entire sets of Seforim, entire sets of the variety that are used seldomly, no longer need to be purchased.
The most recent update includes: Ohr Gedaliahu by Rav Gedalia Shorr. Dibros Moshe by Rav Moshe Feinstein. Minchas Shlomo by Rav Shlomo Zalman Auerbach. Peirush Chai on various Masechtos, Chazon Yechezkel (including Tosefta) by Rav Yechezkel Abramsky and many of the Emes L'Yaakov series by Rav Yaakov Kamenetzky.
I envy the share of the World to Come earned by Rabbi Chaim Rosenberg.
See also this earlier post.
Update May 25:
I didn't notice this at first, but also included in this list are two volumes on Yevamos entitled Nesivos Mordechai by Rav Mordechai Gifter. This is especially relevant, as these are new brand new Seforim and yet are already being posted on HB. I hope this trend continues that authors immediately post their works - upon, or shortly after publication.
Smoky Simon, Nefesh B'Nefesh event at Beit Hatfutsot (video) - In a Nefesh B'Nefesh program with Toldot Yisrael at Beit Hatfutsot on January 3rd, 2017, Smoky Simon discusses the role Machal volunteers played in the Air...
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