A premium version of the popular free Watu WordPress plugin is released.
WatuPRO lets you create exams, tests, and quizzes. In addition the the functionality available in the free version it lets you lock exams for logged in users, randomize questions and answers, select number of questions from a pool, store results and export them as CSV, set time limits, output printable certificates and more.
WatuPRO URL: http://calendarscripts.info/watupro/
The plugin price is $47 and it comes with 1 year of free upgrades and support.