This's Popup Plus skin. It is a part of Dark MI (you can find it here: [link]
and provides you the same Dark and stylish popup notifications as well as Dark MI.
1. Popup Plus plugin (you can find latest version here: [link]
2. imgdecoder.dll (Popup Plus requires it, you can try to find it here: [link]
Note: If you use new versions of Miranda with Avatar Service (avs.dll), this plugin not needed
3. Maximum 10 minutes to install and tune this plugin.
4. Less than 30 seconds to set my Popup skin and ENJOY THEM! 8)
Check out README.TXT for more details
CListModern skin you can find here: [link]
TabSRMM skin here: [link]