Intel’s XDK cross platform mobile development: http://xdk-software.intel.com
Try out ElasticSearch in a ‘fiddle-like’ environment: https://www.found.no/play/
NightwatchJS browser test: http://nightwatchjs.org
Security headers you should know about: http://ibuildings.nl/blog/2013/03/4-http-security-headers-you-should-always-be-using