I have found the Nite Ize figure 9's indispensible. Yes, you can do the same with a trucker's hitch if you can't afford the $10 for a set of the small figure 9's, but personally the Nite Ize are the way to go.

I have the large carabiners I use for tying up my Hennessy Hammock, securing larger loads to my trailer, and securing items to the top of my car on my roof rack. I also have the large and small rope tighteners. They're relatively cheap, easy, and very useful.