Can I run a 10 speed cassette on an 11 speed wheel, but also keep running 10 speed on a 10 speed wheel? I bought a second hand cyclocross bike (running Shimano 105) and I ... love it. I've been doing some short commuting on it as well, but the nobbled tires are copping a pounding. 

I've got a spare set of 11 speed wheels kicking around home that came with my road bike that I upgraded. My question is, I want to put some wide road tires on the 11 speed wheels and keep the CX tires on the 10 speed wheels and just swap the wheels in and out depending on what I feel like doing. 

Obviously I'd prefer not to have to tune the gears every time that I swap the wheels. 

I haven't tried yet because I don't have a spare 10 speed cassette. 

What's the best minimum fuss solution?
Use spacers on the 11 speed wheel to put a 10 speed cassette on. 

See your hub manufacturer's page for details, but its normally a 1.8(5) mm spacer (which comes with the hub, but you can buy separately) and a 1mm spacer (sometimes; which you'll get with the cassette). See this page for a table of some common cases.