I bring my console to my friends house and sign up to Xbox Live (pay through credit card) and download the content from his house using his broadband linking to my console.

Can i do that? Cause i don't have broadband. And i want to get those extra download content for GTA IV

Yes, you should be able to do that, either through his router or his PC (I think you can get a connection directly from the PC into the 360 but I'm not sure).

At the very least, his router or modem in direct connect will let you do it.

content won't be available until 6 months after release right? so you've got plenty of time.

Yes, absolutely. I do the same thing, every time I go online with my X360.

It's very simple, but you can hit some snags along the way:

#1. Depending on the gateway settings, you might need to shut off his computer, remove the router access to the computer, and plug your X360 into his routed (if a router is used).

#2. Turn on your X360. It will automatically attempt to sign into XBL.

#3. You might need to troubleshoot a few issues to sign onto XBL. I know I had to work with DSN settings, IP addresses, and such. I eventually "fooled" the router into thinking that the Xbox 360 was the computer, so it signed me on pretty easy.

#4. Create a XBL account. You DO NOT NEED a credit card to do this.

#5. Add a credit card for Microsoft points. Or you can just go out and buy the MSP at any store, or Ebay and just "redeem code" to get the points. Typically, the later ((Ebay)) is the cheapest route.

The GTAIV content will either be free if you pre-order (supposedly), or will come out in Fall 2008. So be prepared for that.

thanks everyone