[FreeFull]

A big hexagon shape made out of xor gates imitates a xor gate, except that the inputs and outputs are nicely separated. You can omit the inputs as you want.

[JoshTriplett]

Thanks, that works perfectly. Seems to work for 'o' and '+' as well: surround anything with a hexagon of xor gates and it will behave the same on a larger scale, as long as you don't feed it signals too quickly.

[guipsp]

Here's a supersized XOR gate made out of supersized XOR gates.