Hi:
There are alternatives to stream media to your XBOX 360 without WMC, like TVersity(Free) and Playon( free for 14 days, $30 to keep it) the last one includes video streaming from HULU, You tube and Nextflix. Also with the new XBOX 360 update, all you need is to setup your media sharing on your Window media player, which also support AVI and some DIVX's.
In WMP this what you need to do:
1. Click the arrow below the Library tab, and then click Media Sharing.
2. In the Media Sharing dialog box, select the Share my media check box.
Here is a link with more info about this matter:
http://windowshelp.microsoft.com/Windows/en-us/help/7391bdc3-3767-4f98-9Now in order to access your media with your XBOX 360 all you need to do is to go to your Video, Music, or picture Tab on your Dashboard.