From Scriptwiki
Returns filename with the path stripped.
$nopath(<path>)
Examples
$nopath(c:\mirc\mirc.exe) returns mirc.exe
$nopath(mirc.exe) returns mirc.exe
$nopath(\mirc\mirc.exe) returns mirc.exe
$nopath(c:\mirc) returns mirc
$nopath(c:\mirc\) returns null.