The MX Notify Control extension allows you to send customized notifications by emails/PMs based on different triggers - new entry creating/updating, member registration, member validation etc..
MX Mobile Detect is a small plugin that detects if a template was requested by a Mobile Device. You also can detect Screen Resolution!
MX Ajax Detect is a small and simple plugin that detects whether a template was requested by AJAX or not.
Create QR code (bar code) images.
Marker is an EE 2.x plugin that converts between Markdown and HTML. Both directions are supported, Markdown -> HTML as well as HTML -> Markdown.
Locator is an application that adds new opportunities of searching locations in a set radius from the start point. You can make your Store Locator, Places of interest Locator in the region, etc.
A plugin that allows you to set and get custom messages and show them to your visitors in a way you want. E.g. Someone removed something from their shoppingcart, did an action succesfully, etc.