These are the Collection of websites with free medical mcqs in all subjects.
www.mrcophth.com/MRCOphth/mcqbank.html
www.medicospace.com
http://medicalfinals.co.uk/mcqs.htm
http://mcqs.medicalisland.net/
http://www.clinicaltutor.com/
http://www.medicinemcq.com
http://www.medicalmcqs.com/
http://www.allmedexams.com
http://medpgmcqs.blogspot.in/
http://www.medisl.com/
Comment below any other sites you know.it will be added in future