• motor amp-hour calculator

• http://www.taulman3d.com/ claims a high-strength printing filament (comparable to metal -- possibly useful for antweight?)
• The Guerilla Guide to CNC Machining, found via an awesome article from the MAKE Blog.

• These bearings (at least the 3/8 bore one I'm using) will slip-fit over the shaft.  They are not press-fit onto a shaft like a ball bearing. (I put this here because nowhere on the web could I find an answer to this question!)

Robot Hints and Ideas

• DIY high-capacity combat robot safety disconnect
• PID loop links (yes, I got through 12 years and 3 degrees of EE without learning PID loops...):
• PID theory for Segway-style control (accelerometer + compass)
• Video tutorial (part 1, part 2, part 3)

1. In the Security tab of the directory (or file) properties, go to the Advanced properties, Permissions tab.  Select your account or the Administrators group (presumably your account is part of the latter) and Change Permissions.  Make sure you select the checkbox "Include inheritable permissions from this object's parent."
2. Take ownership of the file or directory.  Make sure you apply the ownership to all subfolders and files.

• Clear the CMOS password

• My HTC REZOUND smartphone has what appears to be a propriety USB connector on it, probably to trick people into buying HTC-branded chargers and cables.  It turns out, however, that the jack on the REZOUND (and, presumably, other HTC phones) can accept a standard micro-USB plug (that's the flattest of the USB standard plugs).

• I like to configure Notepad++ so that *.ino (Arduino 1.0-and-later) source files use C++ formatting and *.pde (Processing) source files use Java formatting.  To do this, go to Settings->Style Configurator... and in the dialog, select the language (C++ or Java) you want to configure and at the bottom in the "User ext. :" box, enter the appropriate extension (ino or pde) without the dot and save.
• This explains how to change the default editor for TortoiseHg to Notepad++.  Handy when you want to view a file from an earlier revision (TortoiseHg defaults to using regular Notepad on Windows, but Notepad can't handle UNIX-style text files properly).

• Good explanation of MIDI pitch bend, including setting the pitch bend range
• MIDI Message Table

• Good instructions for flashing a Linksys E3000 router

• Error: "Windows route add command failed: returned error code 1"
• Most likely you are using Windows Vista or Windows 7 (or later) and did not run OpenVPN as Administrator.  Change the shortcut's properties to Run As Administrator and you should be ready to go.
• An alternate problem, assuming the above didn't work, is that the Windows command ROUTE.EXE is in a place where OpenVPN doesn't expect it.  Supposedly adding  win-sys 'env' to your config file should work.
• OpenVPN periodically asks for your username and password to remain connected:
• In your config file (*.opvn) remove or comment out the auth-nocache line
• Be aware this will cache your username and password -- in cleartext! -- in your computer's memory, meaning a trojan/virus/worm/rootkit/etc. could read your password.  Best to use a unique password for the VPN connection.

• Eclipse and the Android SDK:
• when updating the SDK using "Android SDK Manager" you may get an error that the SDK directory can not be moved.  Most likely this is because Eclipse has a lock on that directory.  The fix is to exit Eclipse and run Android SDK Manager by itself (I found it by searching via the Windows start menu).
• adding a Fragment to an Activity associated (via setContentView()) with an .xml gui file: this tutorial uses the line

• Good intro to the timing and composition here.
• Arduino + R/C controller (also talks about channel mixing!)

• The setup of virtual directories is not explained well:
• folder name is what you want to call it and how it will show to a logged-in user
• virtual path is where it will appear in the logged-in user's directory view
• real path is the actual path-on-disk
• So a virtual directory with folder_name="music" and virtual_path="/john/media" and real_path="C:\temp\faves" would present a directory to the logged-in user with path "/john/media/music", which will allow access to the actual directory "C:\temp\faves" 

• Multi-master I2C programming with Arduino
• 0x0 is the general call address -- basically a broadcast of sorts (though with an optional response from interested parties).  Wire.h does not seem to use this directly, however you can use Wire.begin(0x0) on many devices and they all will respond to Wire.beginTransmission(0x0).  (But maybe it doesn't matter which address you use here?)
• Valid addresses for I2C devices are 0x8 (decimal 8) through 0x77 (decimal 119).

• http://www.goldmine-elec.com/: lots of surplus, weird, random electronic stuff.
• http://www.sciplus.com/: much like above
• http://smart-prototyping.com: another site with cheap Hong Kong electronic components
• http://www.e-clec-tech.com/: Random robotics and electronics.  Yet another place to look for stuff.
• http://www.a2zcorp.us/Home.aspx: hobby lathe & milling accessories

• weight estimator for various metals based on dimensions