Opera software has just released Opera 10.5 final for Windows and they claim it to be the fastest web browser for Windows until now. The new release of Opera browser includes a sleek and redefined new design and an improved private browsing.
Also, the new Opera 10.5 allows you private browsing, in a separate tab or in a new window. The new Opera 10.5 also integrates well with the Aero Glass feature in WIndows 7 and Windows Vista.
You can read more about Opera 10.5 here.