The Hubble folk have just released 59 photos of galaxies colliding.
http://www.spacetelescope.org/news/html/heic0810.html
Some of these are just... well... wow!
But the thing that boggles my mind is that despite the appearance of catastrophe on a titanic scale, the distances involved means it is highly unlikely individual stars will even come close, let alone collide.
Come to think of it... isn't that the Andromeda Galaxy just over the horizon???
Humbling indeed...