It doesnt require a 150-year technology forecast to put wireless expectations in perspective. When my sons were watching the movie "The Core," which is supposedly set in the present, I was struck by the ease with which people thousands of miles below the surface of Earth were browsing shared desktops back at mission control. Some things cant be escaped in any century: When youre three times as far from something, youre getting one-ninth the signal strength between any given pair of antennas with any given level of transmitter power. When signals pass around and through steel buildings, or just through people or trees, they get weaker and less precisely defined in terms of things such as pulse width and separation. Dont get me started on the attenuating and distorting effects of thousands of miles of hot rock.Advanced error-correcting techniques, like the ones being used by the Cassini spacecraft now exploring the neighborhood of Saturn, can help. However, there are fundamental limits on information transmission on any given type of channel, and were getting close to those limits now.Do we have to be killjoys? No, but we can still sound a note of reality from time to time. It will help us focus IT resources where theyre effectivethat is, where they can actually do what people actually need. Technology Editor Peter Coffee can be reached at email@example.com. To read more Peter Coffee, subscribe to eWEEK magazine. Check out eWEEK.coms Developer & Web Services Center at http://developer.eweek.com for the latest news, reviews and analysis in programming environments and developer tools.