Malar Azagarsamy wrote an fantastic review of bioorthogonal click chemistry covering thiol-ene, click, and Michael addtions.
M.A Azagarsamy and K.S. Anseth, "Bioorthogonal Click Chemistry: An Indispensable Tool to Create Multifaceted Cell Culture Scaffolds," ACS Macro Letters, 2, 5-9 (2013)