QNT

QNT is a small and fast Win32 editor, distributed with full C++ source code. Its most notable features are essentially no startup time, inserting tabs as real tab characters, and around two billion bugs. You can download both the source code and a precompiled executable in a single archive, but don't complain to us if it destroys all your data.

QNT was written by Teemu Kalvas, but it is no longer maintained or supported.