I have a radiometer, or light mill, sitting on the windowsill at home. It’s one of the coolest gadgets I’ve seen. It is essentially a lightbulb-shaped partial vacuum that contains a set of rotating vanes. One side of each vane is black while the other is white. When exposed to light, the vanes rotate with the black face always trailing the white.
For the longest time, I erroneously assumed that the vanes rotate because of the impact of photons. However, a more detailed explanation can be found on Wikipedia. A more proper explanation for the radiometer phenomenon lies in the energy gradient between the black and white surfaces. Osbourne Reynolds theorized that gas particles tend to migrate towards area of greater heat. In the radiometer, cool particles travel from the white to the black side through the edges, creating a pressure gradient. This gradient drives the vane forward, with the black side trailing. The orientation of the four vanes allow for rotation of the mill. Physics is like magic. I’ve made a video of my radiometer in action:
Many airports in the U.S. offer free WiFi access, although those that do are tend to be smaller airports that you’re unlikely to pass through. Exceptions include the McCarran (LAS), Denver (DEN), and Kansas City (MCI). All other airports usually have a pay-per-use service or monthly fees that are not practical for the occasional traveler who needs to send a quick email or transfer some data. For many travelers these days, however, airport-offered Wifi isn’t even necessary.
A portion of travelers will likely have a data plan on their cellular phones to push email anyway, especially with the growing popularity of phones that mandate a data plan agreement with their providers. With some technical expertise, you could tether your phone to your laptop and surf off of a 3G data network or Verizon’s DataConnect.
What about the average Joe who has a cellphone mended together with electrical tape (certainly does not have a data plan) and usually gets caught up in 2-3 hour layovers at airports? Here are some tips that can help maximize your chances of getting some free airtime during your layover:
At one point, Boingo‘s wireless service had a holey firewall that didn’t really block any outgoing traffic to the web. I was able to append something like `?.jpg’ to my web addresses and jump the wall instantaneously. I believe that they have since “secured” their services, and this trick no longer works. Interesting idea nonetheless.
If you subscribe to AT&T‘s DSL service at home, you are actually entitled to use their airport wireless networks by simply using your login, provided that they are the carrier for the airport. I believe that Seattle, Philadelphia, Cleveland, Raleigh, and St. Louis are just some of the airports that use AT&T.
Some airports have an unencrypted, unbroadcasted networks for their internal use. You can fire up Netstumbler or Macstumbler, identify the SSID, and connect away. I’ve never done this, for ethical and legal reasons. This should NEVER be done, and is listed for academic purposes only. In fact, any business that does this needs to fire its IT department. Security through obsfucation is no security at all.
If you are a member of an airline lounge, you get free wireless inside.
Actually, if you’re NOT a lounge member, you can STILL get free wireless. This is where the money is. Some wireless signals of the exclusive airline lounges extend right outside of the entrance doors. Just park outside the Gold Club lounge and fire up your wireless card. Sure, you won’t get the free booze, food, and leather chairs that airline lounges offer, but you’re also not paying for membership. There are some strong signals outside the club lounges at O’Hare, Midway, San Francisco, Dulles, and Narita. If you have a laptop with an antenna built into the screen (IBM Thinkpad or MacBook are two that do), you will get an even stronger signal.
Be forewarned, if you connect on unencrypted wireless networks, be sure to lock down your system with a good firewall, and be wary of sending sensitive data. You could also route your traffic through a secured VPN. If you stick your hand in a honeypot (or sugarcane), do not be surprised if you get stuck…
Note: The aforementioned information is listed only as a theoretical exercise. Ophthosurgery.COM holds NO responsibility for the content listed here.
Several weeks ago, I experimented with competitive brand saran wrap. There was no doubt that the alternative brand was inferior. Since I don’t learn from past experience, I acquired a roll of brand-X aluminum foil. Fortunately, I also had a roll of Reynold’s wrap aluminum foil, which served as the gold standard in my head-to-head trial of foils.
As usual, the name-brand product was about 2.5x as expensive as the competitive equivalent. At first glance, it was clear that the cardboard packaging on the Reynold’s wrap was sturdier. The perforated sides of the box was cut with precision, allowing smooth unraveling of the roll while creating sufficient tension to keep the roll inside the box. The serrated edge of the Reynold’s box also appeared more substantial. However, I was able to cleanly tear a specified length of foil from both boxes, unlike with the saran wraps. Mostly likely, it’s due to aluminum’s tensile strength. The Reynold’s foil was at least 50% thicker than brand-x, which helps minimize risk of perforation by heavier foods in the oven.
For food preparation purposes, I feel comfortable in using a cheaper brand, as long as the aluminum doesn’t melt in the oven (that should NEVER happen anyway unless there are impurities in the roll). My baked chicken tasted no different with either brand.
Of course as a techie, I also use my aluminum foil as a reflector material for increasing gain on satellite discs. More on that subject in another post…
I like a clean environment. That is, one without dust, dirt, and whatever disease-causing fomites we can rid of without being overly compulsive. This should not be confused with an organized environment. Believe me, I vacuum my living space regularly and keep hospital articles far away from my bed as possible. But I still struggle to keep myself organized. I tend to keep things I may not necessarily need, and objects pile up everywhere I go. I have been trying to purge with little success. Today is an example of what can happen if you don’t.
I have a shoddy bookshelf that I keep many things on–books, papers, trinkets. I had a bookshelf. I’d say a third of its objects were important, like bills, receipts, and keys. I have 2 boxes of books conveniently supporting the bookshelf on both sides. Why that is, I don’t know. Perhaps that’s all $20 will buy these days. I was digging around in the boxes when I heard a crack. The next thing a pile of rubbish was all that was left.
Several weeks ago, I experimented with competitive brand 