I want to second Deane's comment on the usefulness of blogs (wikis). We can TeX, meanwhile, anywhere, anyhow. There could be a very fruitful symbiosis between blog and journal. The blog symbiont is the garden where expositions grow, perhaps fertilized if not seeded by commenters. Each symbiont consists of two poles: medium vs. reader. The journal symbiont faces the problem that its reader can not always write in it (or the marginals get closed away in one library somewhere). So, blogs (wikis) can also serve the marginals, something the medieval libraries knew to value.
This might hint at a new internet gadget. Which reminds me of another gadget: The user-sorted printout shelves, to be set up in and moderated by the library.
...Ooh, could amount to an extremely worthwhile internets programming project, including organizing real paper work, sort, and storage.