Thanks for this thread. As it turns out, my Weirdlands project (at the Patchwork Worlds Wiki) will have a rough adventure path plotted throughout it (that PCs can pick up or drop as they like). I'll be incorporating several of the free WotC downloads, as well as a couple of Drgaonsfoot modules, old Dragon adventures, some snippets from Supplement II: Blackmoor, at least one Penumbra adventure, and some old stuff from Midkemia Press and Grimoire Games (Arduin, baby!). System-wise I'm thinking about using Low Fat Window since it converts to and from other systems easily.
[Edit: Note that the Weirdlands re-directs viewers to places where they can obtain copies of the modules for themselves (if still in distribution), and doesn't spill the contents on the site (specifically to avoid copyright entanglements). Also, it includes a growing and extensive proper bibliography.]