[chopper]

What wtm442 said. Be sure you enable the wireless encryption using either the Wireless Encryption Protocol (WEP) or Wireless Protected Access (WPA) features which come with your router. The owner's manual will tell you how to set it up with a random alpha-numeric password. Put all of your wireless computers on the network using the same password and you'll be set. WPA is the preferred protocol, and uses 128 bit encryption. I don't claim to be an expert, but what I've read said that it is possible to break 128 bit encryption, but would require several years to do so, far more time than the average hacker wants to invest. That's especially true if your neighbor's system is unprotected, which it probably is. I can usually sit in my den and access two or three of my neighbor's systems. You can lock others out of your system, and you can usually even prevent your system from showing up on other's computers.

I have two Macs at home, a G-5 iMac and a G-4 12" Powerbook. Both are hooked up through an Apple Airport Express wireless router, and use the WPA2 security protocol. We also have a hardware firewall since the wife uses her work computer (a Toshiba laptop) to do work at home. The Apple Airport Express will handle up to 10 computers simultaneously and has a port which can hook directly to a printer, so you can print from any accessed computer over the network. The one problem with the Airport Express is that you can only print on the printer; that is, you can't use it to get stuff from the scanner function to the computer via the modem; you have to hook the printer/scanner directly to the computer to scan documents into memory.