c#
https://vimeo.com/154708153 Something C# 7 This Way Comes - Bill Wagner (c#7 wish list is https://github.com/dotnet/roslyn/issues/2136 )
https://vimeo.com/155107766 C# Language Internals - Bart De Smet
https://vimeo.com/155521073 Under the hood of C# 6.0 - Bart De Smet
Practices/Design
https://vimeo.com/156402866 .NET Deployment Strategies (Octopus Deploy)
https://vimeo.com/156264107 Versions are evil - how to do without in your API - Sebastien Lambla
https://vimeo.com/155653145 Distributed Systems principles
https://vimeo.com/155646004 Best Practices for Building a REST-ful API - kevin Dockx
Case studies
https://vimeo.com/156420622 The Times - tools behind a newspaper website (Nodejs, Chef, aws, &, atom-json in S3)
https://vimeo.com/156417164 Azure Portal - tools behind a big SPA
https://vimeo.com/155521095 Polyglot Persistence -Ayende on RavenDb
Javascript
https://vimeo.com/156551919 - ES 2015: The next javascript version today
Security:
Not NDC London, but another NDC event (security day) had several Troy Hunt security talks. Some repetition over the his other talks (e.g. https://vimeo.com/153220272 50 Shades of AppSec), but watch these anyway for a very entertaining and informative introduction to security
https://vimeo.com/154962595 Web Security Essentials by Example
https://vimeo.com/154956509 Both Sides of the Attack
https://vimeo.com/154958732 Lessons from 220 Million Breached Records