WordPress Widgets Shortcode enables you to embed any widget area(or dynamic sidebars) in your posts/pages anywhere using simple shortcode.
Here is the syntax
[dynamic-sidebar id='Name of your WidgetArea/Dynamic Sidebar']
Choose any widget area and copy the name. You just need the name of the widget area/dynamic sidebar as shown below
Insert the shortcode in post and put the name as id in the shortcode as shown below
Check it out
So, all you need to know is the name of the widget area and boom!
Bonus: If your theme has limited no. of widget areas, you can use a plugin to generate as many widget areas as you want. Here is a list of sidebar generators http://wordpress.org/plugins/search.php?q=sidebar+generator