After reading the recently-posted "Build a Metadata-Driven ETL Platform by Extending Microsoft SQL Server Integration Services" article on MSDN, I hunted all over the page for the link to some sort of sample, and there wasn't one! Personally, I'd rather have someone give me a push in the right direction with some sample code after describing such an elaborate architecture. It's not a weekend afternoon project, after all. Turns out the real thing is an internal Microsoft tool ("mETaL") that not only has its own team, but is on version 3.0!
The public future of mETaL is unknown, but as Matt Masson has blogged a few times recently, Codeplex has 2 other samples of metadata-driven dynamic package generation:
While you're surfing around Codeplex, take a look at some of the other Integration Services community projects: