GuidGuard: a plugin that generates C++ style header include guards, using GUIDs for the guard identifier - this ensures you won't have identifier clashes even in larger projects, which traditional filename-based guards theoretically risk.
Switcher: a plugin to switch between 'associated' files. Currently it handles switching between asm<>inc, cpp<>h, cc<>h and c<>h. Useful when assigned to a hotkey.
RegRexPlace: a plugin to do "regular regular-expression replaces". Useful when you have often-used regex replacements. I personally use this when writing posts on forums, so I can use my own simplified markup and automatically generated BBCode markup from that. A sample .ini file is included.