Video 1 (Russia): Bad driving conditions to begin with. The snow piled on the roadsides, the wet-looking road, and the windshield wipers all show that. Traffic going a little bit too fast for the conditions, and vehicles shifting lanes back-and-forth. A recipe for trouble. Add to that a minor accident coupled with some apparently poor reactions --but typical in a driver who hasn't had special training to turn into skids/fishtails (the natural instinct is to do the opposite of what you should!)-- and traffic in two directions with no divider between them, and it becomes a recipe for exactly the kind of tragic disaster the video shows.
Really sad, especially since such accidents should be avoidable.
Video 2 (Norway): Man, that guy in the tow truck was really lucky that he was able to get out safely, before his truck got pulled over. The driver in the semi was lucky not to be more seriously injured, but his vehicle would have been the easier one to survive in. Had the driver in the towtruck been in the cab when it rolled down the hill, there's a higher chance he would have been seriously injured or killed. Also, that COLD water at the bottom might have been a bit closer, in which case it could have been worse, if the vehicles had rolled into it and been submerged... a death would be the probable result in that case. Both drivers were lucky.
Seeing videos like these periodically, is a good way to remind oneself to always, always drive safely! :yes: