Download the MSDN offline docs for Silverlight 3 here. The CHM is nice if you're offline plus it's faster than the online content, has an index, and only contains Silverlight content. The plan is to update this CHM at the end of every month, so stop by when you want to download an update.
Please post a comment if you have any feedback, thanks!
IMPORTANT! If you open the CHM and cannot view content, do the following to resolve the issue:
- Right-click the CHM file, and then click "Properties".
- Click "Unblock".
- Double-click the .chm file to open the file.