I have bottle caps in Johnny-Carson-as-Carl-Sagan numbers: billions and billions. 
And still don’t have enough. 

I sort them as to color.

My single biggest provider: E Z Duz It Hot Spot in Langley, Oklahoma. Proprietress Deborah is a clean freak. The Hot Spot is the cleanest tavern I’ve ever been in, outside a Four Star establishment*. It’s a rare time that I don’t find her laying a scrubbin’ on something when I stop in for my bottle cap supply.  I like getting bottle caps from such an individual. Makes me feel like have standards when it comes to this weird mania. Like I don’t accept just any bottle cap.
Except I pretty much do. I can’t walk anywhere without a quick scan of the landscape. I get a small but distinct rush when I spy a cap. Mostly I pick them up, unless it’s a Bud Light cap. I can tell you without a doubt, around these parts, Bud Light is the brew of choice. Blue caps. They outnumber all others by a bunch to one. Deborah’s stash is blue blue blue. So sometimes, when I’ve got my wits about me, I’ll pass up a Bud Light cap.
Family saves bottle caps and pull tabs for me. Pull tabs are a whole nuther weird thing I like. I return from visits with a suitcase that rattles with caps and tabs. There’s always a note in my suitcase that the TSA picked my luggage to open and paw through. Any more I’m surprised when I don’t find the note. 
When friends come calling, or we cross paths, they offer their saved caps. It’s touching. 

Certain sophisticates are closet cap fiends, they share their caps with me. You know who you are…Brian.
When Trader John’s family went to Mexico, the nieces and nephews took time out of burying Uncle Stretch in the sand to comb the beach for bottle caps.

The Toews Tribe stops at Pops 66 when they’re on the road. Jerry pushes down his natural inclination for shyness to ask for caps for me. Pops 66 is pop and bottle cap heaven. I dream about rolling around in a mountain of Pops 66 caps almost as frequently as I dream about being locked in a Lowe’s overnight. Let me be clear: these are dreams not nightmares.
I use bottle caps in my art.

Bottle caps make up my tres chic line of jewelry.
I use bottle caps on interior walls of my house.

*I’ve never been in a Four Star establishment in my life.