I pretty much have two distinct systems, although "system" may be a strong word for my work environment. In my main personal system (Google Tasks and calendar, and Evernote), I have a single context "Work", which is almost empty. I only use it for things I need to do at work that are not part of my normal responsibilities.
For work, I'm either working, or not. As a developer, I need my desktop and network access to do anything, so I'm either at my desk, or logged in remotely via VPN. I have a list of projects with actions managed in Onenote, and Outlook\Exchange for contacts and appointments. Project documents are stored on a network drive, accessible from where ever I work. I do sync my Outlook appointments to a separate, dedicated, Google Calendar that I include in my own personal calendar, to I get a complete view of my schedule.
It is simple to separate for me, as I'm generally doing work assigned and prioritized by someone else. Anything not in my assigned pipeline is personal, and goes in my system.