Heroku/Herokugarden - in terms of teaching my students how to deploy an ecommerce app in less than an hour (actually 31 minutes). This would have taken A LOT MORE TIME if there was no such thing as instant deployment!

http://www.youtube.com/watch?v=D0WhxO0W_n4 http://www.youtube.com/watch?v=vt0RHqRHyvA http://www.youtube.com/watch?v=aUG4mf29ZQ8 http://www.youtube.com/watch?v=UE2YkzKPf0o