Soft liquid shape

Hi, i would like to know if is already exist a plugin or script/expression to create or simulate liquid or soft geometry. For example, the video : http://vimeo.com/32916842 at 5 secondes look like this. Also : http://vimeo.com/56956819 at 2,5 sec, the shape look like soft!

Thanks

I hope someone understand want i'm looking for

Alex