It has just came to my attention that Marxists.org will be offline for a couple of weeks. A statement from the website:

In early November we came under sustained denial of service attack from Internet hosts in China attempting to exploit a misconfiguration in our server's operating system. The nature and origin of the attack, our previous history with the PRC, and the experience of others suggest that this maybe politically motivated and directed by the Chinese government.

[...]

As if that weren't bad enough, while attempting to make arrangements to buy a new server, we learned that our colocation facility will be closing on February 1, leaving MIA literally homeless.

[...]

The bottom line: there is a significant probability that we will not be able to find and deploy an acceptable solution in time to meet the February 1 lights-out date. This means that the MIA will be off the air. We will make every attempt to bridge the gap with the help of our dedicated mirror operators though we may need to stop serving some of our more "expensive" content such as MP3s and PDFs. There is also a chance that our ultimate solution may require us to make a long-term evaluation of the type of content we serve and make things like PDFs available via alternate distribution channels (e.g. BitTorrent). However, despite our recent litany of seemingly fatal problems, the MIA remains a strong organization with a wealth of content, committed to providing the premiere electronic library of Marxist writings. Despite the political, technical, or economic pressures, rest assured that we will find a way to keep these works available to the world.

Mirrors can be found at:

Asia
France
Germany
Russian Federation
United Kingdom
United States (East)
United States (South)