Making a WiFi TV receiver and that too from a can, looks a bit weird to me. Though it is not that difficult as it sounds and you may be able to make it in an hour or so and that to by investing just $35 in the making.
The device was made using some easily available parts except one audio/video receiver that costs around $25 and was imported from Canada.
If you want to make one for your own purpose then CLICK HERE for the PDF instruction sheet.
Check out the Video on the procedure