One of the most convenient features of XBMC is that you can automatically download subtitles for any video right from inside it. It would be really nice to have this feature with VLC. And it can be done using the VLSub extension:
Create the directory ~/.local/share/vlc/lua/extensions/ and place the Lua file there. This is where VLC looks for its extensions.
Play any video using VLC. Choose View > VLSub, this shows the VLSub dialog.
Choose either Search by hash or Search by name. The extension searches in OpenSubtitles and displays the list of all matching subtitles. Select the subtitle you want and click Download. Once the download is done, click Close.
The extension downloads the subtitle file, places it in the same directory as the video file, renames it to have the same name as the video file and applies it to the currently playing VLC. Enjoy :)
Tried with: VLSub 0.9, VLC 2.0.5 and Ubuntu 12.04 LTS