By three methods we may learn wisdom: First, by reflection, which is noblest; Second, by imitation, which is easiest; and third by experience, which is the bitterest.
by Confucius

My talks at IMPA (streaming videos)

Geometry of Gelfand-Cetlin integrable system (Conservative dynamics and symplectic geometry  2009):

http://strato.impa.br/videos/workshop_geometry/geometry_070809_03.avi

Dynamics on Poisson manifolds (Poisson 2010):

http://strato.impa.br/videos/poisson/poisson_26072010_nguyen.flv

(now that I listened to my own talk at IMPA, I found that my English was really horrible !)

For all video lectures recorded by IMPA:

http://video.impa.br