Web resources for Laboratories, Virtual Manipulatives
Shodor Educational Foundation: http://www.shodor.org/
National Library of Virtual Manipulatives: http://nlvm.usu.edu/en/nav/vlibrary.html
NCTM Illuminations: http://illuminations.nctm.org/
WVU IML: http://www.math.wvu.edu/~mays/AVdemo/AVdemo.htm
Larry Green (Lake Tahoe): http://www.ltcconline.net/greenl/java/index.html
Tom Leathrum: http://cs.jsu.edu/mcis/faculty/leathrum/Mathlets
Cut the Knot: http://www.cut-the-knot.org/index.shtml
MERLOT: http://mathematics.merlot.org/
MathDL: http://mathdl.maa.org
Virtual Laboratories in Probability and Statistics (Kyle Siegrist): http://www.math.uah.edu/stat
Math Archives at University of Tennessee (Knoxville): http://archives.math.utk.edu
Duke collection of sites: http://www.math.duke.edu/education/baltimore/sites.html
GeoGebra: http://www.geogebra.org/cms/
All time champion: http://www.google.com/