for all you DIYrs , here is a template to cut your normal SIM to a Micro SIM form factor. Micro SIM is supported by many handset manufacturer.
A simple template is available here as PDF, go ahead and give it a try.
Original post: http://www.stochasticgeometry.ie/2011/10/13/n9-unboxing/
you have to Scroll down to see this DIY.
P.S. do read his other post, really interesting blog.