While I do game (well, I research games, so ...), I prefer to use my desktop for other things too. The screen real estate and ergonomics are far superior to any other device IMO. Using a laptop on a desk makes my neck and back hurt. On my lap, even more. I do use my phone for web browsing more than I should, given my neck issues. But it's far better than a laptop on my lap. From time to time I browse the web on my TV using my HTPC, but that's usually when I'm too lazy to get off the couch
At work, I use a docked laptop with a display and mouse. Works fine. If I didn't have an external display, I wouldn't be able to work.