Here’s an interesting idea. I haven’t installed it, but the description I copied below almost makes it sound like a type of user-requested spyware! This toolbar will pay attention to the page you’re on, and in some instances will tell you whether or not you’re allowed to use the content depending on the license your institution has.
How does it work?
The instant the user’s browser accesses any online content, the toolbar looks for tags that publishers have embedded in the content. When the toolbar locates the tags, the iCopyright symbol on the toolbar changes color to reflect the type of license available to the user.
If the user’s company is covered under a site license, the iCopyright symbol turns green and reads "Site License." If a one-off, pay-per-use licensing service is available from that publisher, the iCopyright symbol turns yellow and reads "Single License." If the toolbar finds no tags and no licensing mechanism enabled by the publisher, the iCopyright symbol turns red and reads "Request Permission." The user simply clicks the iCopyright symbol on the toolbar to transact the license or submit a request.
Link: iCopyright Toolbar Download. (IE6 only)