I'll start.
Did you know that Wil "Wesley Crusher" Wheaton's first credited acting role was Martin on the Secret of NIMH animated film? That was probably the last time he sounded assertive and tough in an acting role too, and he was both a little kid and a mouse. :rat-salute:
from Blade the line about "some motherfuckers are always trying to ice skate uphill" was inserted by the writers into the movie after hearing Wesley Snipes say it in personal conversation to a friend on set.
Amazing!