i suppose it will be like in the old days where 1 dollar would buy you something worth like 75 dollars worth of corn/tobacco/shovels/etc... think 1800's.
So they would talk about parts of a dollar.  I think the value of BTC is just getting to be where this will be a real concern/convenience.

Ironically... we used to say "That'll be 2 bits" or a "two bit theif" ... there meaning 2 bits worth .25 dollars.  I had an uncle that in the 80's still would complain that phone calls shouldnt cost 2 bits when the regular price went from 10 cents/call to a quarter.
Now we are saying a BITcoin is worth blahblah... what will we call the bits of BTC?  hehe!
Is a bytecoin worth 8 BTC.. and a word coin 4... and we could have blockcoins and such!
Actually I think the use of uBTC is already being used some... just till now with the current values rising might it be seen more.