Kate Russell's weekly review of new and interesting sites and apps.
is a huge archive of educational videos and exercises covering everything from algebra to venture capital.
is an organisational tool shed to help run a business, covering everything from sales to document management and customer relations.
is an Android app bringing a social twist to storing and sharing QR codes.
Microsoft is trying to entice Android and Apple users to switch platform with
an online mobile demo
that gives a taste of the Windows experience from any handset.
And finally, Facebook has released a
list of the top 40 most shared
stories for 2011.
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