Air Video Can Stream Videos to Your iPhone and iPod Touch

Automated server discovery on local network using Apple Bonjour
Possibility to add custom servers by specifying IP address and port directly Can be used to stream videos over internet (see the appropriate section in FAQ)
Share disk folders and iTunes playlists
Optional password protection
Add videos to iTunes playlist from iPhone

Videos that can not by directly played by iPhone can be easily converted. All major containers and codecs supported (mp4, m4v, mov, avi, wmv, asf, mpg, mpeg, mkv, 3gp, dmf, divx, flv). DRM protected videos as well as proprietary codecs are NOT supported.
Live conversion allows you to play videos without having to convert them upfront.
Requires iPhone or iPod touch with firmware 3.0 or newer and sufficiently powerful computer.
Option to convert entire video before playing it (offline conversion)
Files converted offline can be put to conversion queue
Adjust quality, zoom and resolution for each video individually
Select audio stream (language)

Setting Up Air Video

You need to download and install Air Video Server.

Once the server is running, add folders that you want to share. If you have videos in your iTunes playlists, you can also share those playlists.

If you have been running Air Video Server before the window will not open. You can access it using Air Video Server icon in menubar (on Windows the icon is in system tray).