DIY wireless antenna is really easy actually. You can tweak your existing coax cable and make it as your tiny little wireless antenna for your laptop and boost wireless signal. Wireless.gumph.org has creating a complete tutorial to make a DIY wifi antenna using coax cable. The procedure to do that requires only coax cable and a standard N-Male connector. This is suitable for those who want to increase the signal strength of their wireless camera and this is alternative to the pringles cantenna which is much larger.
Laptop Wireless Antenna | wireless.gumph.org