Propano is a small package that allows to parallel more task that concur to
the construction of a single object assembled from various remote resources
like web services or databases.
Propano only waits for the remote resource when it is
necessary,parallelizing the requests when possible.
Typical use is in the construction of a web page for which different objects
must be taken from different places (e.g. various RSS feeds).

http://zef.homelinux.org/vqwiki/jsp/Wiki?Propano

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