- URIs:
    + As defined in RFC 1738.
    + More of them.
- Dates:
    + localtime dates.
    + ISO Dates.
    + An inverse of strftime?
- numbers:
    + Decimal numbers (e.g. 7.5, 0.3, .99, 15, but not 1.23E5).
    + Roman numbers >= 4000. Unicode?
    + Prime numbers? Fibonacci? Other special numbers?
    + Ranges of numbers.
- postal codes.
    + Lots more, especially British and Canadians.
- Email addresses.
    + RFC 822/2822.
