Vista

Basically the subject line says it all. If you want working AV today, go grab this free copy.

https://www.my-etrust.com/SubscriptCenter/MSTrialRegistration.aspx?cid=1855&lang=en-US

Want to help the Vista team make sure that the Media Center Extender experience on the Xbox 360 is great?

You have an Xbox 360 connected to the Internet?
You have a PC capable of running Vista Ultimate or Home Premium?
You are over the age of 18?
You reside in the US?

If all of those are a "Yes",

Sign up here:
https://mscuillume.smdisp.net/Collector/Survey.ashx?Name=MCE_beta_recruit01

Originally spotted here: http://www.majornelson.com/archive/2006/05/19/Sign-up-for-the-Media-Center-Extender-for-Vista-Beta.aspx

I typically try to avoid the VZAccess software whenever I can due to the special Venturi software likes to mangle the TCP-IP stack/helpers from time to time. Another blogger has a step by step instructions on avoiding the software.

Basically, under any OS, as long as you can get the PCMCIA cards exposed to the USB layer to provide the USB serial interface, dial #777, use xxxyyyzzzz@vzw3g.com for your username, replacing xxxyyyzzzz with your mobile number. Password is always 'vzw'.

You can also 'drop down' your connection speed depending on what init strings you send to the 'modem', unfortunately a lot of those are card specific. One primary use of this is to force 1xRTT mode when you are in a fringe area.

More info here:
http://blogs.technet.com/keithcombs/archive/2006/04/30/426857.aspx