What do you do if you're lying in bed watching a movie when you remember that you need to schedule a meeting with X for tomorrow at 11am? Do you get out of your warm bed and pull out your work laptop and add the calendar entry and then climb back into bed or do you just pause the movie, log in to your work calendar and make the entry real quick before resuming the movie?
The closest I've ever had to making this a reality was when my work computer was an iMac so I'd just leave it on 24/7 and RDP into it from home (I lived within WiFi distance of the office so all this was done via LAN). Even then, when the work stuff was going to take more than ~5 minutes, I'd still end up doing it natively from my home computer rather than deal with RDP lag.
edit: I also really struggle with what IM programs to keep on my work laptop these days. Medium of communication doesn't map cleanly onto work/personal contacts so I either deal with friends pinging me while at work or missing vital messages from people expecting a business response/having long professional conversations using a phone keyboard.