It's from an English school in Katowice (pronounced Cat-O-Vit-Sa appararently) in Poland which he visited over the weekend.
A little closer to home - Hull - was the following spot from Nick Cooper taken over the Bank Holiday weekend:
We cross the pond with the next couple:
"This one's on the front of a gallery on Marcy Street in Santa Fe, New Mexico. Note the adobe and vigas -- typical southwestern U. S. architecture. Not the kind of place you'd expect to find the Underground roundel." Nicely spotted by M. J.
Here's a spot from Middlesboro, Kentucky, kindly sent to me by Lisa A
Finally we go down under to Sydney, with a spot from Paul Holloway:
He said "I spotted this recent when I was on holiday in Sydney, Australia. Sydney doesn't have an underground metro system (at least not yet), but some of the stations on the central loop are below ground. Wynyard is one such station, which is where I took the picture of the Concourse Bar. I didn't have time to go in the bar unfortunately, but I'm guessing that the use of the roundel is likely to be a nod to the fact the bar is in a below-ground railway station. It didn't look particularly well patronised!"
Thanks to you all and if you'd like to see more of Roundels not on Underground they're here. If you spot any in the flesh on your travels, please send them in to me and I'll blog the best in a future post.