MSDN is free (to download)

This monstrous library choke full of information for the developer of Windows applications and (preferably, but not only) using Microsoft development tools was – up to now – only available in a paying subscription. This was a strong limitation for those developers not serious enough to invest in such a tool.

Microsoft decided to change its policy about distributing the MSDN Library. Everything is now free and downloadable (about 1.6GB anyway).