I was trying to figure out some details about how laser time of flight sensors determine distance, and Sam’s Laser FAQ came to the rescue. What a terrific resource for geeky hobbyists.
The simplest laser to build from scratch would appear to be a variation of a design from Scientific American’s Amateur Scientist column, but this one requires no glass work and no vacuum apparatus, and can be built for $10 (plus a high voltage power supply).
Slashdot provided a link to KiteCam Disaster Fund Appeal, the website for an individual who lofted and subsequently landed a Casio EX-3 digital camera using a kite. To pay for the folly of his poor engineering and inadequate kite flying skills, he now has resorted to pleas for money. Frankly, I think giving money to someone who destroys cameras is kind of silly. Why not send money to individuals who actually can repeatedly send cameras to high altitudes without destroying them?
The grand daddy of all kite photography places on the web is Charles Benton’s Kite Aerial Photography. Awesome stuff, and local to boot. KAP in Amarillo, TX also has a bunch of nice photos, including 360 degree panoramas. Awesome.
If you click on the tiny photo on the right, you can see a cool photo of San Francisco just after the 1906 eartquake, taken from a captive balloon from about 2700 feet.
Jim McCarthy writes about 21 Rules of Thumb that guide the development of software products inside Microsoft. There are very few surprises, but I’ve been involved in quite a few software products before turning in my leaf and becoming a TD, and I bet most product managers would find more of them surprising than I did. McCarthy has a very pragmatic and practical view of software engineering, and serves as a good counter-agent to the marketing hype of most software companies.
Marie Sandström has a short thesis on spoofing biometric fingerprint scanners. It involves collecting latent prints, and then casting a replica finger in gelatin. I have read about such techniques here by Tsutomo Matsumoto, and here it is two years later and the latest hardware appears no more effective.
K3PGP has a nice website which I’ve seen before since he and I share some common interests: astronomy and lasers, notably. He’s got an interesting page on his K3PGP Experimenters Corner that detail his experiments with laser communications. Basically, he created a beacon transmitter which transmits 30 second long pulses of particular frequencies spaced 0.5hz apart. This modulates an IR diode, which flashes up to the night sky. Five miles away, he targets the region with a PIN diode laser reciever, which is fronted by a 12 inch Fresnel lens. Incredibly enough, he can easily receive characters sent this way. It’s very slow speed (two chars per second), but it’s a neat trick.
Picture this: you run across a reference to a patent that you want to read, but you are too cheap to spend the money that the U.S. Patent Office charges you to download images of the patent in question. What do you do? Apparently you use pat2pdf, a cool bash shell script that downloads TIFF images from the U.S. Patent Office and neatly assembles them into a PDF file. For instance, check out this patent which originally spawned the search for such a gadget. Much thanks to Oren Tirosh for writing this useful little script.
For reasons which escape me, Yamaha has a really nice webpage on paper crafts, which include patterns that you can download and build. These include not only cool motorcycles, but also animals like the Japanese macaque or the yellow-eyed penguin or the Cape penguin, pictured at right.
The patterns are all available as PDF files which you can download, print, cut and assemble. Neat! The motorcycles are especially well done, it’s really incredible what you can do with paper models.
I like arts and crafts, particularly those with a mathematical bent. Wholemovement – The Work of Bradford Hansen-Smith shows what cool stuff you can do with paper plates. Be sure to read the commentary about the “wholeness of circles” and the like. I’d like some of whatever he’s smoking. Found this while perusing the terrific Geometry Junkyard, which I noticed now has an RSS feed. I’ll be adding it to my list shortly.
I enjoy an (admittedly waning) interest in the Photoshop contests on fark.com, and recently they ran a contest where the theme was Find Nemo somewhere unexpected. A cute idea, with several ideas that were pretty damned funny. One of the most hilarious to me was this one, which is a spoof of a particular photo which has been showing up on my Yahoo! page as the most e-mailed, seemingly for weeks.
Any tinkering I’ve done with neural nets is a decade or more in my past, but I’m still interested. Python News! provided this article on Hopfield networks as an intro, and the author and David Mertz wrote another that is also of interest.
A nice collection of photography links can be found at DIY for photography links. I particularly liked the instructions for making your own Shroud of Turin, the GL-Cam page, and Gene Rhodes’ photoprojects.net.
Clifford Wolf wrote VHDL to implement a custom processor which executes the Brainf*ck programming language using a Spartan 2 FPGA chip. You can download the VHDL source and test cases from Clifford’s Homepage. Nutty stuff.
Sweet Zombie Turing! Adam Dunkels has written phpstack – A TCP/IP Stack and Webserver in PHP. Some people really do have too much free time on their hands.
Adam is also the author of the more useful lwip and uip, which are compact implementations of TCP/IP that you might actually want to use.
Writing software in odd languages isn’t exactly a new idea. Nanoweb is an http server in PHP. HTTPi is a webserver written in perl. PS-HTTPD is a webserver writen in PostScript.
Tom Van Baak has a fascinating obsession with timekeeping. His website, www.leapsecond.com, has a great deal of information regarding timekeeping and his vast collection of odd and accurate timekeeping devices. He even wrote a nice paper which details the state of the art in amateur timekeeping. The short of it: amateurs can achieve ridiculous accuracy for fairly cheap amounts of money.
Oh, and he took some photos of the Venus transit too.
