Wireless Network Adapter
There are many wireless network adaptors available on the market right now. Wireless Network adaptor is different for each type of computer. For example if you are using desktop pc you might want to use Wireless PCI Adapter see the picture (Linksys WMP54G).
PCI is a (Peripheral Component Interconnect), an industry-standard bus for attaching peripherals to computers.
If you are using notebook, there is a slot for the PCMCIA Card Wireless Network Adaptor which is sometime come with the omni-directional antenna with it. But normally it is just a card, where you can just plug in into the slot provided. For example Linksys WPC54G
The popular one is the Wireless USB Network Adaptor . This is among the best choices for those who need plug and play network device. I just bought D-Link DWA-130 Wireless N USB Adapter which has the much higher capability then wireless b/g type. If you want to increase the wireless signal you can try the homemade DIY wireless signal booster.