If you have Javascript enabled, then there are several places that should work: the Sir Robin LifeWiki article

http://conwaylife.com/wiki/Sir_Robin

the original link (via the Show in Viewer option), or the Catagolue page

http://catagolue.appspot.com/object/xq6_yyocxukcy6gocs20h0a3...

(click on the knightship in the upper left -- the word "Launch" should appear when you hover over the image).

They all use the same LifeViewer to do the animation, though, so you're out of luck if Javascript isn't available.