I've got more than 30 devices using wireless radio frequencies in my house. The first thought I had when I realized how large the number had gotten was "Since Microwave ovens use RF to cook, perhaps all the other radio frequencies around us are heating up the world. Maybe THAT'S what's causing global warming!" Every one of those devices uses electrical power, and all generate some heat. Tripple whammy since in the summer that means my air conditioner has to work harder to keep the house cool, drawing even more electricity from the coal burning power plant that feeds my town.
The latest technology I've purchased uses BlueTooth. I've got bluetooth dongles on three PCS and a bluetooth adapter for my iPod. They all allow me to listen to music off themselves via bluetooth with my bluetooth headphones: http://www.bestbuy.com/site/olspage.jsp?skuId=8480413&st=insignia+bluetooth+headphones&lp=1&type=product&cp=1&id=1185267960408
I'm still looking for a bluetooth receiver I can plug into the rear of my home theater amplifier so my iPod can send it's music there. Any minute now. I love being able to walk about untethered while still listening to music, podcasts, or audio books. As such I will not give up my bluetooth devices for the sake of global warming. ;-)
Almost everything else that is wireless in my house could be wired. I may in fact go about running wires to those things that don't really benefit from their wireless ability. The garage door remote will have to remain, but it is only a momentary wireless signal. The wireless phones can go, and good riddance! I've worn out four different wireless phones in the last 5 years, and none of them worked well when they did work. The wireless router will stay, but mainly because it links my music collection to my iPod and a couple of laptops that don't always stay near a hard cable.
Clearly wireless technologies are becoming more and more prevelant in out homes. Cell phones are more boon than bane. They can stay. I imagine that all those RF signals are doing us some harm. Some day the medical society will get back to us on that one with "Oops! We didn't realize...".
My bluetooth headphones are what I call a "killer application" of the technology. Every technology needs a killer application, but not all RF applications are that useful.
I'll predict that the next version of the iPod Touch will have bluetooth. It would be even sweeter if it had a set of bluetooth earplugs with it. ;-) The only awkward thing about all the iPods is that danged cable you have to drape from your ears to the device. They already have bluetooth in the iPhone so it's not like the technology is beyond them.
One more thing the iPod Touch needs is a way to access shared music on the owner's home network. There is no reason why my personal music collection has to travel down a cable and is limited to the 8 or 16gigs of space on my iTouch. I can already listen to MP3s posted on the web without downloading them. If you're listening, Steve Jobs, get this done!