My Granddaddy drank his coffee from a FireKing Jadite mug for all the time I can remember about him. Granny gave me my first taste of coffee when I was 3, and it was one of our “secrets” that Grannies and Granddaughters share. Some years after my Granddaddy’s death, my Granny gave me one of his Jadite mugs for Christmas. When I got home I made myself a cup and when I put the spoon in to stir, it made the delightful tinkling sound I remembered from 30 years ago. I immediately thought, yes, this is what coffee sounds like. That is the bestest sound for me. The sound of coffee - a spoon clinking inside a Jadite mug.
The sound of a strong thunderstorm at night on your roof as you’re curled up in bed, reading a good book.
Beautiful, HockeyMonkey. Makes me wonder what happened to the old Jadite mugs from my grandmother’s house.
The sound of ice skates on ice.
A lawn mower outside (as long it’s not 07:00).
Baseball cleats on cement. (Golf shoes sound roughly the same but don’t usually involve well-built young men in tight pants… 
)
The crack of a wooden baseball bat.
Thunderstorms.
My dog smacking his lips about 6 times as he prepares for sleep
Trains - the rumble of a train slowing to come through town, its horn echoing across and along the valley at 4 in the morning.
Tam-tams and gongs - I just love the sound. Washes, crashes, the sound when you hit a Tam-tam really hard and then lower it into a tub of water. I heard a piece 20+ years ago by James Tenney called “Koan - Never Having Written a Note for Percussion” that consisted of a 12 minute roll on a tam-tam going from inaudible to deafening and back. Exquisite to hear live.
The absolute bestest sound from my childhood - the sound when you hit the Coca-Cola sign that hung out front at Hurl’s Foods with a snowball. (No, I’m not making that up.) I swear, when you got that sucker just above the hyphen, it said ‘Om’ for about 30 seconds. We used to get rowdy and climb on each other’s shoulders to hit it with a mallet, but the sound was never anywhere near as good. It was a sound you had to earn.
The squeals of young children at play.
Distant church bells.
The distant train horn, which, to me, always sounds like that orchestral moment of tuning up before the conductor raises his baton and silence falls in the hall.
Sounds of the night in the tropical jungle.
The ocean.
Rain falling hard on the roof.
The sound of the wood catching fire after striking the match.
And, being short of stature, the heart beating in those I hug.
I love to listen to little kids amusing themselves. The voices of the characters, the sound effects, the occasional phrase that makes you say, “where the hell did he hear that? Oh yeah…that might have been* me*.”
Horses clop-clop-clopping.
Really violent storms.
Spanish guitar.
I was also touched by **Hockey Monkey’s **story. You write beautifully. Thanks for sharing that.
I love the noises my dog makes when she’s sound asleep and dreaming-her little legs look like their slightly running and she makes these tiny little barks and yelps. So cute.
I also love waking up to the sound of a neighbor mowing their lawn.
Oooh, one more… the sound on “Law & Order” when they change from scene to scene.
I know, I know, it is weird!
Oh, Hockey Mokey’s was wonderful.
Can I borrow it?
Rain falling on a tent.
The geese and swans returning for the winter. Some times they honk all night.
The sound of snow falling.
An old-fashioned wooden bridge over a creek o a dirt road - the type with rough horizontal planking. In the countryside, late at night, you can hear a truck coming for miles, changing through the gears, then it hits the bridge: brdbdbdbdbrrbdbrbrbdb and then starts changing through the gears again for a while, and then it’s gone and you hear the silence. I like that feeling of another human being being out there in the wilderness.
My Favorite sound is the sound of you and your sweetie making love in ABSOLUTE SILENCE because your buddies are ten feet away outside the tent.
That and Sandhill Cranes.
Lightsabers
I’ve lived within hearing distance of a train for as long as I can remember. I love the sound of a train going by, though in this house I’m close enough that it’s really not so enjoyable if I’m outside.
A cat’s purr
and, I’m not sure I’d call it the bestest, but I can always hear my mother approaching because of the keys jangling off her purse. It’s soothing as well, I guess.
The alarm sound on the Death Star - it’s not quite an “ah-ooo-gah” horn, but it’s close.
Bagpipes
Wind blowing autumn leaves
The gurgling and drips of coffee brewing.
The sound of my daughter singing when she thinks no one is listening.
Waves rhythmically sloshing against the hull of a boat or the surf pounding a sandy beach.
Heavy snow falling and the accompanying dampening of all other noise.
Cats purring and my dog sleep whimpers.
Ping pong balls hitting a paddle or ping pong table.
Hula hoops that have the noisemakers inside.
The sound of really sharp hedge clippers or scissors.
Church bells and windchimes.
The wind rustling the trees in the fall when the leaves are drier or brown leaves blowing down around on the ground.
Someone else biting into an apple.
Mockingbirds.
Wow! These are beautiful contributions!
I have to get on the (dog)wagon and add that I also adore doggie snooze noises: lips smacking, sleep murmurings, and whimpers.
I guess so. Whatcha gonna do with it? 
Thanks for the other compliments Mahna Mahna and Tikki.