How to Open Links to Web Pages Right in Mac OS X Mail

"Let us say," says Vannevar Bush in the July 1945 issue of The Atlantic, "the owner of the memex is interested in the origin and properties of the bow and arrow."
The device would let its curious owner consult an encyclopedia before offering more from an authoritative work of history. "Yes!" "When?" and "Osage orange?" are but some of the comments the memex owner has — and jots into the desk and system, "linking [them] into the main trail or joining [them] by a side trail to a particular item."
This, of course, reads curiously like an early form of the Internet and web — where you can follow side trails from emails right inside Mac OS X Mail, for instance, as far as a particular arrow and bow will carry:
›› Is that link and LOLthing worth a longer look? You can take a quick glance at linked pages right in Mac OS X Mail. Here's how.