I only have a 20gb HDD for my 360 and I'm running out of space because I like to install few of my games to my HDD that I play most so they load faster and the console doesn't sound like a lawn mover.. HDD that I ordered is 250gb and it's only $55.70 so it's pretty cheap because it's obviously fake but what I read it's working just as good as the real ones and there's no errors or anything, but few guys said it's only 120gb but they just put 250gb sticker so it would sell better, I don't know.. But we'll see.
Other thing that I ordered is a fake USB rechargeable battery thingie for your controller so you don't need to play with your batteries all the time. I know M$ is also selling those
but they sell them for like 20 bucks or something and this fake one is only $5.70, so just guess which one would I buy..
Links to products I bought:
250gb HDD - http://www.dealextreme.com/details.dx/sku.30815
USB Rechargeable Battery thingie - http://www.dealextreme.com/details.dx/sku.26461