Is there something similar that is based on Wifi connections instead of bluetooth? Wouldn't that offer a greater range?

Edit: Nevermind, the article explains that firechat does in fact use Wifi in addition to Bluetooth to transmit messages:

  From the first IP, I understand that Firechat is also looking to create bond
  between WiFi device. It periodically sends UDP packet to the multicast
  address 239.192.0.0 and will also forward message just as it does with
  bluetooth. So not only every message sent are forwarded by bluetooth, they
  are also forwarded by WiFi !