Good Informational Websites

Over time I have been creating a list of links that contain good information online or via PDF's explaining theory, selection guides, how to's etc. on PLC's, motors, valves, flow meters, math and so forth and I am always on the look out for good information. Google is a great thing however unless you have hours to look through hundreds of links you never know what you may miss. I am just curious if you people have come across great informational links to share regarding plc's, instrumentation etc that you have found to be a great resource.

Thanks!

Rookie,
There are a few good plc forum sites that I like, this does not imply that they are the best but I like them, I have also attached other sites by using these you can do almost anything, except build a thermal nuclear rocket, but I have a company Smoke and Mirrors inc. working on this one.


PLC related
http://www.plctalk.net/qanda/ You found this one
http://www.patchn.com/
http://www.mrplc.com/
http://www.control.com/

Programming related
http://www.thecodeproject.com
http://www.visualbasicforum.com/index.php

Engineering search
http://www.globalspec.com/

Engineering tips
http://www.eng-tips.com/index.cfm