Suppose, you have a custom Magento module and you wanted to add a custom tab to “Customer My Account” section, i.e. the frontend part displayed after customer login.
Here is the solution:-

Problem:- I recently upgraded a Magento shop from version 1.6 to 1.7 and suddenly the Google Analytics stopped tracking data.
Solution:- You need to add ‘template’ attribute to googleanlytics block in app/design/frontend/your_package/your_theme/layout/googleanalytics.xml

This article contains code snippet to get customer attributes in Magento.
Get Customer Collection

This article contains code snippet to get custom options value of all products in any Magento order.
Suppose, there is a product with a custom option dropdown list. You chose one of the option from the dropdown list and purchased that product. The code below fetches product’s custom option value selected in any particular order.
Here is the code:-