How divisible are bitcoins - the technical side

Hey,

So there is another thread asking about bc and decimal places. It is stated that the client(s) only show 2 decimal places, but there are 8 in total. Now, working on stuff, I find that it would be nice if I could transfer at least 4 decimals precision, but the full 8 would be great.

Looking at the code it seems simple enough to remove the rounding from bitcoind, but what about the receiving side? If it's a non UI client, then it will show everything, but would I be making things overly confusing for GUI clients?

Is there any shortcoming in me patching my client to handle full precision?

Will transaction fees be applied to transfers above 0.01, but with more precision? I wasn't aware of it being that way.

And yes, I am rounding for now, but I like things clean, and I can either allow withdrawal of higher precision amounts, or I can round to 2 decimals the prize handout, I just rather do the former, that's all.

And no, it's not *only* for the sportsbook. I have plans...