I've always had lots of ideas, just none I've wanted to follow through on, now I'm in the early stages of an idea I think will be useful ( at least it will be for me ). It's an idea that was simplified out of another idea that's just too large for me to tackle at the moment. In fact it's an idea that's been part of a variety of other ideas. It's also part of a number of other peoples products, and is probably one of the trickier bits of their products, but it's not a product in itself.

So, at the moment, my market size is at least 1, because I want it.

Odd thing is, given I have free range on everything, I'm suffering tech choice anxiety, which is slowing me down a bit.