Countries by Borders or World Capitals Proximity in 90 seconds
Typing a capital will highlight all the other ones within 1,000 km (and the corresponding countries). Typing a country will highlight all the bordering ones (and the corresponding capitals).
Nice idea, might use a little more time, though: Even with an optimized list (does someone find a possibility with less than 48 names?) in another window to just re-type it into the answer field there's only 9 seconds left.
I finally managed to do 191 !
And if you want to appease some Greeks, maybe fyrom for North Macedonia
Pretty good, but type ins need help.