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  • Alden
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Important note: It's Gbps, not GBps. The throughput is measured in bits, not bytes. If the drive controllers were capped at 1.5 gigabytes per second, no one would be complaining. However, 1.5 gigabits per second is only 187.5 megabytes per second, which is easily saturateable by SSDs.
One would think, but WinMo6.5 is really just 6.1 with a revamped interface. Save the new Today screen and threaded text messages there's not much better about it than 6.1. I've been running it on my Herald-based phone for a while and while it is better, it's not nearly as good as Android, iPhone OS or (and this one is guessing, as I've not used it) WebOS.
I'm hoping it's cheap to use it exactly as you described. Toss that thing in the entertainment center, put Linux on it and use it as a music/video server that you can administer remotely or directly.
Why does the hand model have the HTC logo on her fingernails?
jon-
No, it really matters. It is true that with strong enough magnetic fields you can pull things that aren't ferromagnetic, but you need A LOT of power and you can't pull nonferrmagnetics with nearly the force that you can pull ferromagnetics. There's no point to not using the best material, especially when it's cheaper than the alternatives.
maveric101 - OH NOES YOU GOT ME WITH AN EQUATION. By your logic, using a capacitor for anything but quick storage and release of energy is misusing them. The underlying principles of matter and energy that allow a railgun to work don't dictate what you need to use it for. People have suggested using them for space launches, and I doubt anyone would bother launching small things into space.

Also, you run into problems at high speeds that you may not be aware of. First of all, there is a terminal velocity for given set of rails and caps at which they can drive any object. If you hit this velocity and you've still got the wattage left over, it makes sense to upgrade to a heavier slug. Second, smaller projectiles are harder to keep on course than larger ones. Ever heard of bullet tumble? Imagine it at eight times the speed of sound. Third, railguns actually kinda suck. You waste a whole lot of energy in the friction between the rails and the slug, usually converting part of both of them to plasma (which means replacing the rails after enough firings). Coilguns are better because the only energy loss in a properly made one is the resistance of the wiring and the internal resistance of the slug.
Like others have said, it's a coilgun, not a railgun. Also, the "point of a railgun" isn't just to shoot tiny things very fast. It's also to shoot big things very fast, or if you had rails long enough you could use it to move a train very fast. It's simply a method of making something move using electricity. The point of it is whatever you design it for.
Wrong. Copper is conductive, but it will not work as a coilgun projectile. You need something that is magnetically active, like iron, steel or cobalt.
Quantumphysics -
There's no way that the cap in a disposable flash is going to have enough juice to pop just from being shorted with no load once or twice. I suppose I could have said "grab a spare computer fan and short the cap through it" or something like that, but for a relatively low power, soon-to-be-trash project like this it's OK to be rough on your passives.

Also, why a railgun? You waste so much energy turning the projectile and rails into plasma.
OK, where to start? Coilguns work because when you apply a current to an insulated coil, you end up with a magnetic field. If you push more current through at a higher pressure (those in the know call this "voltage") you get a stronger magnetic field. So, what can push a whole lot of direct current (DC for those of you playing along at home) through some wire really fast? Well, batteries can so the whole "a lot of current" thing, but they can't do it particularly fast. This is why we use capacitors. They're like batteries that can release all of their stored energy all at once. So, all you really have to do is wrap a bunch of wire around a barrel of some sort, attach either end of the coil to a capacitor and a switch and let it fly.

The absolute easiest way you could make a coilgun RIGHT NOW is to grab a disposable camera with a flash. Pull the flash circuit out (don't shock yourself now) and identify the charging switch (it's probably two metal contacts side by side), the battery terminals (durrrrr) and the capacitor (It'll be the biggest thing on there. It might have some writing like 250uf/320v on it. In any case, it will be a cylinder). I'd solder a piece of wire across the contacts for the batter charger, just to make it simpler. Now take a screwdriver with a plastic or rubberized handle and use the head to tough both of the leads on the capacitor at the same time. If there's a spark, you did it right. If there's not, it just means that the cap wasn't charged. ALWAYS BE CAREFUL WITH CAPACITORS. They hold their charges for a long time and it can hurt like a bitch/kill you if the capacitor is big enough. Now make your coil. I used a drinking straw that was just big enough to fit a copper-clad steel BB with a tiny bit of room. For those who don't know how to wind a coil, read this:http://www.angelfire.com/electronic/funwithtubes/Coils-1.html
OK, so now you have a coil on your barrel, yes? Stick something in the straw (I used a bent piece of aluminum) so that when you slide your projectile in it will stop just after/just inside the coil. Now connect one end of the coil to one of the leads on the capacitor and hook the other end of the coil into the other lead on the cap through a switch/button. This will be your trigger. Load the sucker up, charge the capacitor by putting the batter back in it's place and flip the switch. If it doesn't work it means you messed up. Keep in mind that if your projectile doesn't react to a magnet it's not going to work.
Let the hive mind of Engadget get that for you.
"I'm looking for a wireless trackpad to use with my older (2.5 or so years old) C2D MacBook that's perpetually docked to my home theater. Something sleek, thin, not too small, made of high quality materials. Ideally, it would natively support all of (Snow) Leopard's multitouch inputs, and even more ideally, it would have a charging dock / base. The only problem is that I'm not sure that such a thing even exists. Think you can throw me a bone?"
 

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