I couldn't resist buying N+1 using "Christmas justification" a few minutes before I saw this thread.
I've been wanting to trial a Dutch bike in Bikeability teaching locally - lights, rack, chainguard, lock, back pedal brake etc. so it's eminently practical for flat central London teaching.
A Twitter link took me by chance to a Gazelle Cheetah 24" Dutch bike. I Couldn't resist at £25 reduced for 'Black Friday weekend' from £100.
It's collection only, but as it happens, it's fairly near where my sister, who's been asking what I want for Christmas, lives.
So, Christmas present sorted, collection sorted, delivery sorted.
Can't wait to trial it in some schools.