Not all videos are up yet, a few I may add in a second link dump. I saw most of these live, but several are worth seeing again. See also my slides/github rep link dump
.net
https://vimeo.com/153745433 - The changing state of immutability C# - Jon Skeet
https://vimeo.com/153900560 - What does an "Open Source Microsoft Web Platform look like?" - Scott Hanselman
https://vimeo.com/154034601 - A brief history of ASP.NET: From 1.0 to 5.0 - Damian Edwards and David Fowler
Security
https://vimeo.com/153220272 - Troy Hunt, 50 Shades of AppSec
https://vimeo.com/153908385 - Making Hacking Child's Play - Troy Hunt
https://vimeo.com/154041158 - What's new in Security in ASP.NET 5 and MVC 6 - Dominick Baier
https://vimeo.com/154172925 - Introduction to IdentityServer - Brock Allen (not actually asp 5)
https://vimeo.com/153102690 - .Net Core Authorization Stack - Barry Dorrans
.Net Core (Asp.Net 5 at the time!)
https://vimeo.com/153212604 - .Net Core CLI, Damian Edwards and David Fowler
https://vimeo.com/153749266 - Middleware introduction - Scott Allen
Practices
https://vimeo.com/154049610 - Knowledge Work Culture - Michael Norton
https://vimeo.com/154312751 - Testing with No Harm - Enrico Campidoglio
https://vimeo.com/154301830 - Case Studies in Terrible Testing - Todd Gardner
General
https://vimeo.com/154588594 - Docker - Mark Rendle
https://vimeo.com/154025470 - Mark Rendle, Everything I know about computers, I learned from the movies