Create Custom Activities for SharePoint designer workflows: http://msdn.microsoft.com/en-us/library/dd819165.aspx
WPF MVVM Sample applications: http://tanguay.info/web/index.php?pg=notesItems&id=28
Fields Validation for WPF using MVVM pattern : http://www.tanguay.info/web/index.php?pg=codeExamples&id=212
Input Validation in WPF MVVM: http://karlshifflett.wordpress.com/mvvm/input-validation-ui-exceptions-model-validation-errors/
Dispute Finder, A Firefox Add-in to highlight disputed claims in web pages (Still Experimental ) : https://addons.mozilla.org/en-US/firefox/addon/11712
Emad's Blog 