I realize I've subconsciously ended up doing this with spaces on Mac OS. I have a set of "Productivity" spaces and a "Goof off" space and I've been trying to toggle between the two in 5/25 minute splits. I even end up running a work browser and a personal browser. It's ended up working really well, but the addition of a chess timer seems like a brilliant idea to keep me from getting too drilled into Wikipedia rabbit holes.