Just thought I'd post this as I recently upgraded my Samsung NC10 to wireless N (better connection, better range for my router) for £35...and it was an easy job. Thought others might like to know what I bought and how I did it...
I looped the thrid antenna around the space surrounding the hard drive, there's abolutely no need to open the screen casing. Actually, the further away the 3rd antenna is from the other two the better - for optimum Wireless N signal.
The entire upgrade took less then 30 minutes.
I used to get 11% signal in the front room (looong way away) and connection drop-outs every 10 minutes...it's now 55% strong and I haven't had a single drop-out.