In the last week my 2-year-old MacBook has developed an odd and increasingly frustrating problem -- hoping someone has advice: When the laptop gets more than about 5 feet from the wifi router it's using (whether the one in my apartment, or the one at my sister's place, or the one at the coffeeshop) it loses the signal. In fact, it doesn't just lose it - once about 20 feet away, it can't even find the signal. Even sitting next to the router, it only registers 4 bars, not full strength... I'm pretty certain it's my laptop's problem, as my buddy can have no problems in our apartment with his (older) MacBook. Ditto my sister at her place. I'm a computer moron, so I've tried the basics, to fix this (turning the connection on/off, mucking with the preferences). Nothing's helping. Anybody got a diagnosis/prescription? I'm a freelance writer and my computer and access to the Web is my life, so I'm increasingly worried about this. Thanks.