How do I remove a stuck kitchen aerator tip?
If you look closely, many aerators have a couple flat spots on them, that you could tighten an adjustable wrench on to.  That or a strap wrench would have been my first tool.  But failing that, and the lack of desire to preserve the original finish, the curved jaw vice grips pictured above should work.
The next level, replacement wise, would be to file some flat sides onto the doomed aerator and use a wrench.

Dave.