This is XPTable component (advanced data grid) designed by Mathew Hall and published on www.CodeProject.com. Since Mathew isn't upgrading it any longer, I decided to put it on sourceforge so everyone could add something to it.
A really good table control that is customizable without too much effort. The visual designer support is okay, but could use some work. If you need a lightweight and free! table control, then this library will do the job in most cases.