There's no way you can pull them together into a virtual journals collection. But if they are inter-operable, you can. Professor Harnad is tweaking his CogPrints archive software so that, within six months, any university will be able to use it, free, to compile its own archives in any discipline. The key to its success will be the willingness of academics to input their papers. But the whole impetus is coming from the academic community, in part as a backlash against the prices for journals charged by traditional publishers.
Researchers have to use journals to spread word of their work and make an impact academically.
The refereeing is done for free, although there is a cost to administering it. But the main costs to publishers are in the editing, printing and distribution in paper form. From time to time I write to publishers and ask them for reasons for substantial increases. Publishers said they were keeping the cost per page fairly constant, he said. Their editorial boards are receiving ever-increasing numbers of papers from the academic community that they feel ought to be published so the number of issues and number of pages per issue is constantly increasing.