EDIT: Forgot about the rolling hitch. Perfect when you want to attatch some guy line to another. This also works great with a quick release loop.

I also want to add the alpine butterfly to my arsenal (adds a secure loop to the middle of a roap). I just have to keep tying it so I remember.

My list is soo much shorter... but it get's the job done:
Bowline hitch
Sheet bend
Trucker's hitch
Round turn with two half hitches
Overhand knot and figure-8 knot

More often than not, I'll augment any of these with a quick release loop.

Setting up a tarp ridgeline (or clothesline) I'll make a bowline hitch with quick release around the first tree and a trucker's hitch around the second. I really like how quick and easy it is to get a nice and REALLY taut ridgeline with this method. And two gentle tugs is all it takes to tear it down again...

For joining two ropes I've gone off square knot. Tying a sheet bend with a "quick" method is much faster and much safer, and works for ropes of uneven diameter. Sorry, I'm unable to find videos or pics of my "quick method" for tying a sheet's bend.

I use round turn with two half hitches if I don't want a loop, but want to tie really taut to whatever object I fasten to. This is also my preferred knot for mooring boats.

I really dig fancy knots, but this short list is what I actually use and rely on. Anything fancier and I'll have to look it up...