I can't find the thread or the post, but I once came across a post on Touring about the neat stuff you can find in a discount or dollar store to use ion a bike tour. The list included lights. While I wasn't able to find dollar store bicycle lights, I did find some items I can use:

Insulated lunch bag
packets of instant oatmeal
zip ties and bungee cords
bicycle cable lock

Any other goodies to look for?

Bandana? Sun protection (and other toiletries)?

Nylon stockings. I cut them into squares and sewed three edges to my panniers to make stretchy outside pockets.

A tiny proximity alarm. The alarm consists of two side-by-side pieces, one mounted to the window sash, the other to the casing. It is designed to sound when one piece moves more than a few millimetres from the other, as happens when the window slides open. (I was not able to make it work reliably on a bike).

Crazy Glue. For "instant" repairs. Always in plentiful supply at Dollar Stores!

Sometimes they have really cool athletic socks that are perfect for cycling.
When they do have them in stock, I usually will buy them all. =)

Some other stuff you can get-

Sunblock/lotion
playing cards
notebooks/journals
pens
pots/pans (cheap = lightweight)
beanies
electrical tape
matches
tupperware
coffee mugs

Also, I've found some killer deals on stuff at thrift stores. Found an entire camp cook set for .75.

OK Neil,

I will help your search, but not all the way since my memory is shot. Unless typing this helps me remember.

I can't remember her user name... but she is a regular poster, a randonneur, lives in Canada at the moment as I recall and has posted a list of wondderful items found at the dollar store. Posts regularly in this section, and in the Long Distance Cycling section as well...

I know when I see her name I will think "no kidding"

In fact, I will think it right now.... Machka... No kidding!!!!! She listed several items in a posting...

I knew it would come to me right as I gave up!

Looks like the specific message I recalled mentioned specifically winter gear:

https://www.bikeforums.net/showpost.p...47&postcount=7

Well, I was going to say something about that being my thread ... but I think Little Darwin beat me to the punch!