dachshund

Camelbak, Garmin with heart rate monitor, Take a Look mirror on my glasses, a bell.
Not an accessory per se but custom built wheels are awfully nice.

Papa Tom

Mirrycle MTB mirror. I can't believe I rode on the street without one for so many years. Best $15 I ever spent on my bike.

Edit: Also, the AAA-powered mp3 player and AA-powered speaker on my handlebar (total = less than $35 about five years ago). These have added immeasurable joy to my commutes and to my overnight rides.

DropBarFan

Clip-on aero-bars are great, add comfort esp on longer rides & can hold other accessories.

canklecat

Yup, I feel nekkid without it. Tough too. It's survived a few falls with barely a scrape on the outer edge.

bulldog1935

back to the original post, I hate padded gloves - they create circulation pinch. I hunt out Giro Zero gloves on sale everywhere I can find them.

My favorite - spiked platform pedals for sport/ touring bikes. Let me ride with any shoes, move my feet around, and they stick like velcro.
With its low bb, and my ice-skate feet, my favorite on my old Raleigh are Blackspire El Gordo.
On my CX frame with its higher clearance, my favorite are Raceface Atlas.

On my near-vintage road bike I'm still riding clips with Binda straps (stiff enough for easy loading) and old style riding shoes (san cleats) with shanks (Chrome sneakers in the summer, and Mamnick leather for winter).

Deal4Fuji

As I was wringing out the water from my wrist sweatbands last night, I thought of this thread. In the +100° heat index we've had for over a week now they're an essential part of my riding equipment. I use them year round cause if I'm not sweating in hot weather, my nose is running in cold weather. I have about 20, bought cheap from Ollie's for .99¢ a pair. Nice quality too....I guess someone at the manufacturer left the San Diego Padre design on too long. They had a lot of them, all with Padre logo stitching that I turn inside out.

irwin7638

This came up in a discussion at the local club once. An experienced club rider and racer said his powermeter was by far the most useful accessory he had ever had. I thought and decided that the Pletscher mousetrap rack is by far the most useful item I have ever had. I've used one on at least one of my bikes for nearly 50 years. I can't say that about any other accessory.

Marc

DropBarFan

Never tried wrist sweatbands, would have thought they're a 70's/80's affectation but OTOH on hot-weather rides it's harder to brake w/sweaty fingers; for all I know it could be from sweat trickling off arms. Gotta try lever covers, extra grip would be nice for cold/rainy or hot/sweaty conditions.

wphamilton

My aero commuting box is the accessory getting the most use lately, but it's not worth the cost of development to this point.

I'd have to say for the literal worth the money, the rear rack on my ss/fg is the most worthwhile accessory. And the fenders on that bike.

lwb

Schwable Marathon Plus - on these, I've had one flat in 11 years of commuting (replacing them every 3,00 miles or so).

GeneO 

Take-a-look mirror.
Halo Protex headband
Topeak micro clip-in seat wedge bag.
Serfas 60 lumen taillight (they now have 80).
Garmin 500

I usually don't leave without any of these.

.

james_v

Mirror and rack on my recumbent!

dim

crane brass bell suzu .... best sounding bell in the world ... I use it at least 6 times a day to warn other cyclists or pedestrians that I'm passing ... even guys with headphones jump out of the way ... I have 4 bikes, they all have one installed

Connell

Lights? Lemme tell you about lights. Here's what we had in Britain in the '80s. (1980's, smartypants.)



Four D Batteries in each of those things. D batteries I'm tellin' ya! The pair of them weighed more than I did. Not only that but the front one bounced out of its bracket at the merest suggestion of a bump while both of them stopped working if you were foolish enough to ride with them in the rain. Having them on your bike, assuming they were working, meant you were in compliance with the law but that was the only practical purpose they served.

You kids with your fancy schmancy LED lights. You don't know you're born. (Waves fist at clouds and wonders once again why crotch is wet and warm.)

Anyway, seeing as you asked, my favorite doohickey would have to be my bike computer. All those years I didn't have any way of quantifying how much fun I was having.

Cychologist

My latest purchase is a PowerPod. https://www.dcrainmaker.com/2016/03/powerpod-depth-review.html

Cheap for a power meter and seems to work pretty well.

DropBarFan

A nice-sounding bell helps, I went to 3 LBS's before finding one that sounded decent though I think it's aluminum or steel, the Crane brass bell must sound better. I think a bell is more pleasant than hollering "on your left!" & the Crane bell lets one control the volume vs many other bells.