A month that swings either way.
Not a good example because “…flied out to third” is based on the noun fly (ball), not the verb fly, so you expect it to have a regular preterite. The computer mouse is based on the noun mouse and therefore ought to preserve the strong plural, so mice. Of course, current computer mice lack tails, so perhaps they should be called voles.
A month that goes both ways?
Edited to add: Dammit DrDeth!