I've been thinking about this whole "unrealized gains" thing...
How are they supposed to implement this?
How can you tax something that technically doesn't have accessible value? 

If my $1000 investment has unrealized gains of $100 and they want to tax that... 
(assuming I'm broke and can't pay that out of pocket) 
I'd have to sell 100 dollars worth of my investment to cover? 
So then THAT sale is now a taxable event too?

How is this a reasonable solution?