If any error is encountered, have a fallback chain which will be invoked.
For instance, you may specify that you load scripts from a CDN location... but if any of them fails to load, forget the CDN and instead load scripts (in the fallback chain) from an alternate (possibly local) location.
+1 really would love this, been having problems with JS failures with our CDN.
+10 We want this Kyle!
I'd love this!