Ok, this is such a newbie video, but I wanted to post it anyway. I used a video camera, blender and icarus to put it all together.
[video]http://youtu.be/Ode-fZumIJo?hd=1[/video]
It’s better than a chrome sphere on a checkered floor anyway. 
Not too shabby 
There are only really 2 things I think it could use to take it to the next level. 1st and most important, I think you could spice up the animation on it. Have the boulder bounce and tumble a little. Unless it was perfectly round, it wouldn’t roll that smoothly. 2nd, I think you could work on the surfacing a bit. Maybe mix in some finer detailed photo textures to emphasize it being actual rock as opposed to looking like painted paper-mache.
The lighting and compositing actually look really good. You could probably lighten up the shadow under the boulder just a bit… try to match the shadows of the kids a little more, in both darkness and color (the kids’ shadows are tinted brown, the boulder shadow is just grey/black). And if you wanted to really really push it, you could add in some light wrap but I don’t think it would be needed except maybe the last 5 seconds.
Very well done, esp for a first match/composite project
-David
Despite myself, I couldn’t help feeling a little bit worried for the kids, so I guess you did a pretty good job on the realism 
Sorry about my ignorance, but, what does icarus do?
That’s very impressive! Nice work!
And great advice from DMRadford. You could perhaps use Blender’s rigid bodies physics to get a nice uneven roll.
very nice work.
not bad. could have been longer with somebody getting run over. xD
Where can Icarus be downloaded?
Try th links on this page
don’t know if they are legal though… Be careful
Véri nice, guys!
Nice, thats pretty cool.