Counterfeit currency is only low on your list because the governments are working hard to prevent it.
If it was possible to print notes that could not be easily detected as counterfeit -- millions would be printed and it would devalue the entire currency.
It's possible to print notes not easily detected as counterfeit in the field with a lot of today's currencies. It's not very practical on a large scale in the long term because the government is intent on preventing introduction of meaningfully large amounts of fakes and has teams tracking these bills.
So bitcoin can't be devalued by "printing" fake "bills." That's a good prerequisite, but it's not a practical improvement for me over the current currencies.
> So bitcoin can't be devalued by "printing" fake "bills." That's a good prerequisite, but it's not a practical improvement for me over the current currencies.
Well, the value in bitcoin is that it can't be printed by anyone, even the goverments, uncontrollably - there will be only specific amount at max in circulation at specific time.
This might not be valuable to you, but it certainly will be for many else. Many people don't like the thing that goverments keep devaluing their fiat currencies.
Roughly on the order of $1 a year. I'm not going to lose sleep over that.
http://www.fin.gc.ca/budget06/bp/bpc3d-eng.asp names the amount for National Counterfeit Enforcement Strategy in 2006 as $9 million. I don't think these are the total expenses on preventing counterfeits, but it's within an order of magnitude. The official population count in the 2006 census was 31,612,897, so let's say the number of people who have paid any tax that year is around 30 million. Corporate taxes would complicate the "per taxpayer" calculation a little bit, but they would only make the amount smaller.
If it was possible to print notes that could not be easily detected as counterfeit -- millions would be printed and it would devalue the entire currency.