What a tangled web LOTR weaves...
 

One of the beautiful things about LOTR is that everything is linked in some way... one such example is how Pippin looks into the palantir, which in turn makes Gandalf and Aragorn aware of it, which sends pippin to minas tirith, were he eventually saves faramir from burning. Also, aragorn, looks at sauron and makes him attack to fast. Did you notice any other such linked cases?

Bilbo gives Frodo mithril coat, coat saves him twice.

Merry, Pippin captured. Aragorn & Co. follow, help defend Rohan.

Gandalf confronts Balrog, Gandalf dies, Gandalf comes back as the White.

Really everything in the story is linked. Tolkien was good at unity throughout his work, which is the mark of a skilled author. In my opinion it wouldn't be as good of a story if there were a bunch of things just sort of left hanging off to the side.

Good call. There's links all over the world of Middle-Earth, in particular between Frodo's quest and other things happening with his friends at the same time.

There's also many links across time, such as Aragorn and the Dead Men. Almost nothing is completely random, and every character or object seems to have a history. Bombadil is really the only random thing in the whole book if I'm not mistaken, and he has no real influence on other parts of the story. A complete tapestry, to be sure, much like our own world.

WarBringer, you might also be interested in thisthread.