This application solves the problem of not wanting to go to Reddit and get distracted, but still wanting to get private messages from people you know on Reddit. It could conceivably be skinned to look exactly like Outlook and therefore work as a ‘Boss Button’ type app, but that type of thing has already been done.
It uses jQuery, Bootstrap, MarkDown, and the Reddit::Client perl module
The back end polls the Reddit Messages API to pick up new messages via cron
and the front end polls the back end via AJAX. Just like Outlook, it will beep and rebuild the message list pane on the left as soon as a new message arrives.
I can't actually show you this without signing you up via OAuth or letting you read my personal mail, so here are some screenshots: