Alright so I just bought Xbox360, and was wondering if i want to play Xbox Live connecting to the internet via wireless router do i need the Xbox 360 Wireless Networking Adapter?
simple answer - yes i believe there is an off-brand that now makes the wireless adapter so you can save a couple 20 bucks instead of having to pay the full $100 for a new microsoft version...
best bet is to go to ebay to get the wireless adapter, they're usually going between $40-30 less there.
Doesn't the 360 have a hard-wired ethernet port? If so, a wireless bridge might be a better - and cheaper - option. If you have (or might have in the future) additional network-enabled devices at the same location, they could all hook to the bridge, but only the 360 can use the wireless card.