Most SwissCards from Victorinox include a removable nail file with a screwdriver tip..
The nail file has a roughened metal surface which works quite well for taking rough spots off fingernails or toenails. The tool is hard enough that it probably won't ever wear out.
The SwissCard nail file is nearly identical to the nail file with a screwdriver tip found on smaller Victorinox Swiss Army knives. Except, of course, this nail file is removable.
A few Leatherman tools also include a nail file.
This tool is found on the following SwissCard models: