One antenna that has increased in popularity is the windsurfer antenna. It is very simple to do, and it will increase your signal at least 10 percent. You can either attach it to your wireless card antenna or to your router antenna it works either way. I would write an article on how to do it, but instead I found this youtube video that explains how to build it.
You can get the print out model for the antenna from this site: freeantennas.com
click picture to view video!
In this tutorial I go over the process of cracking wep encryption for wireless network. Here I demonstrate why configuring your network with wep encryption is not such a good idea, as anyone with the right tools can crack it in a manner of minutes
Some history first:
There are two types of WLAN vulnerabilities, vulnerabilities due to poor configuration and vulnerabilities due to poor encryption. WEP was the original security standard used with wireless networks. Unfortunately, when wireless networks first started to gain popularity, researchers discovered that WEP was flawed, in which an attacker could defeat WEP because of flaws in the way WEP employed the underlying RC4 encryption algorithm.