Quite a bit further than 500 km; think 600 km (Amsterdam–Berlin) to 1000 km (Amsterdam–Wien). And that is leaving out the additional distance one might travel onwards or towards the night train's stations.

indeed longer distances are within the broader proposition of a night train network. leaving earlier in the evening and arriving before noon almost doubles the distance. though this comes at the expense of a shorter day.

now about that shift key... I think I read somewhere that capitalization is a relatively recent invention (like after 1000 AD). people used to do all caps and then they invented all lower case and then somebody had the idea of complicating things by mixing the two :-)