This CodeLet Sends an email after a node of specific content type is created. The CodeLet uses Drupal8 API which sends and email upon node creation. This CodeLet implement hook_entity_insert & hook_mail.
Place this CodeLet on your MYMODULE.module file. 

This CodeLet will display a block content in a region programmatically. You have to implement hook_preprocess_HOOK() in THEMENAME.theme file of your theme directory.

This CodeLet display related products of cart items on the Onepage Checkout at the bottom.

Follow steps to add related products on the Onepage checkout page.

1. Edit the onepage.phtml file located at /app/design/frontend/default/your_template/template/checkout
2. Add the following code end of the file:
    

This CodeLet will redirect the user to checkout page when user clicks on 'Buy now' button on the product

Use the code and create a custom module

Make sure you keep the weight of the module high in "system" table
 

This CodeLet add already implemented  "Pass ids as arguments to page" on VBO. 
Place this CodeLet to your custom module, you can see the customization on Bulk Operations field  on the image.

This CodeLet will ajaxify the respective element and will trigger an event. Respective action will be taken by the code and displayed on the form within the specified wrapper

This CodeLet allows to add products to cart from code. The current product uses an extra text field. The cart view has been modified to accomodate extra fields from the product

This is just a two lines of CodeLet which allows you to redirect your users after they log in to your site. This not complex and super quick

This CodeLet will Dispaly poll choice radio as a Button and view result on click of button.

This CodeLet allows to set the user password during Rule execution, the following process can be used.

1. create user entity ($newuser)
2. set a rules variable $password (use PHP code to generate a random string)
3. execute custom PHP which looks like

This way, you can also use the variable $password in say, an email to the user letting them know what their automatically generated password is.