Here is a summer school on Berkovich spaces
http://www.diffusion.ens.fr/index.php?res=cycles&idcycle=490
(there are more courses at http://www.diffusion.ens.fr/ but unfortunately they are not broken into catergories; one has to fish for mathematical courses more or less via manual search)
The following links lead to lectures in Russian.
http://bogomolov-lab.ru/SHKOLA/courses.html
a summer school for undergraduates (topics include number theory, metric geometry, anabelian geometry)
http://www.mathnet.ru/php/presentation.phtml?&option_lang=eng
has a huge collection of videos, including recordings of summer school courses both for undergraduates and graduates.
http://blip.tv/pifagorov/ and http://www.lektorium.tv/ are examples of a similar effort