I thought about using little blackboards.
And I thought about using wood, like the bits i used on tables.
Instead, I bought some little wooden numbers, some little wooden bases, some super glue and some orange paint. It all cost me about $15.
(^ Our tables had to be numbered by row, not table. Hence the 2 numbers on one table!)
What other table number options are out there I wonder...Please share any interesting ideas you've seen!