Notepad++ 5.8.1 now out, with upgraded Scintilla editor component
Notepad++ is a great open source text editor. In addition to being open source, it's extensible and incredibly nimble for a beast of its power. I often use Java-based jEdit or XUL-based Komodo Edit, and compared to those two, Notepad++ is blazing fast.
The Notepad++ team released 5.8 a short while ago, but it was worth holding out on the upgrade -- because they've now released 5.8.1 with a couple of important bug fixes. The most important feature for 5.8 is that Scintilla, the open source text editor component that Notepad++ uses, was upgraded to the most recent release (2.21).
There are also two new line wrapping methods added, enhanced macro capabilities, and many other incremental improvements. If you use Notepad++, now would be a good time to kick the tires on this new release.