I've managed Linux Servers (usually poorly), currently manage hundreds of physical and virtual Windows Servers (usually somewhere between poorly and moderately well), manage multiple enterprise-class Cisco Routers, Switches and Firewalls (got that down-pat), and build an enormous amount of software (usually moderately well).
I specialize in business applications, and applying a broad spectrum of business rules across a broader spectrum of languages (all the .NET web stuff, as well as PHP, Python, F#, C++, C, and Fortran - yes, it's still out there, yes I hate it). I also build physical hardware devices on occasion, and tinker in electronics and PLC-based systems, mechanisms and solutions.