Which "Like" plugin is this?

[Reminisce32]

What is like "like" plugin that is used at vBSEO's forums as you can see in this post where it says "djbaxter likes this": http://www.vbseo.com/f2/status-vbseo-55663/index2.html#post339482

[exel]

It's part of the vBSEO system.
It has its own Like System.