Well, I'm not the only one out there doing this kind of a project. Also you have to remember that costs are spanned over many years (probably at least 10 yrs), meaning my average annual travel (leisure, that is) costs don't skyrocket. It's anyway about choices and doing what feels right for oneself. I have already some 20 countries done, so I don't start from zero.

Actually I have one golden rule: at least one overnight stay at some form of accodomation means a proper visit and is counted as a country checked off my list. So I'm with Maluku_Flyer on this. Plus it's nuts to travel to somewhere like Vanuatu and then just leave the same day. Crazy waste of time and money.

So yes, I don't count e.g. layovers and transfers. Suprisingly the most tricky one will be the Vatican - there's not a single public guesthouse, hostel, hotel etc. within the borders of the Holy See. Nada. So I guess I'll have to settle with just walking there.

Of course I could go really hardcore and sleep as a homeless hobo in the necropolis to get that magical box ticked off the list.