Content delivery networks

I am authoring an article for Amazon Cloudfront. Are there recommended
techniques for working with content delivery networks in Rails?

I have seen and used ActionController::Base.asset_host and am aware of
the date parameter that Rails can attach to each static image to
reflect its last modified time.

Are there other build techniques and coding techniques to work well
with CDNs? For instance, does anyone refer to fixed IDs in code which
are replaced during a build with the latest and greatest version of an
asset? If so, is this a rake task?

I'll do some Googling, but thought I would ask peers, too.

The article will be based on Rails, so will assist the community at
large when published next month.