Your question seems to have two parts. The first:
jopatac wrote:Can the Eye-Fi be used with a wireless cell phone?
Sounds like you want to know if the card can transmit photos to a cellphone with wi-fi. The answer is no. The card doesn't do peer-to-peer (ad-hoc, device to device, call it what you will) networks currently.
Now as far as this question:
I have friends who want to know. From the Samsung Eternity Forum. The question was asked: "Have you guys seen those Wi-Fi cards? I think they are Eye fye or something, but they fit into the microsd card slot... I was wondering if we use those to access Wi-Fi.... "

Two problems with this idea. First, this is a full size SD card - I haven't seen a cell phone with a full size SD slot in ages. Eye-Fi doesn't offer a mini or micro SD version and possibly never will - there's just not enough real estate in the smaller versions for everything that makes this work. The second problem is that Eye-Fi is not a general purpose wi-fi adapter. It
only transfers photo files (specifically JPEGs) and, with some versions, video files from a camera to a wireless network. There's no provision for using the card as a generic wi-fi device.