Know enough x86 assembly to take a look at a crash dump and know what could be going on.
Also know a (tiny) bit of Linux.
Took part in the development of software such as:
-Win32 desktop applications
-TAPI service providers
-user interface controls
-various COM components
-web pages and web applications
Also participate in (either actively or contributed to) the development of various Open Source projects including:
- BString, Better String Library
- Kepler Project