Army trucks. 

I have lots of vintage things in my collections but the vast majority of it is lighting related (lamps, fixtures and gear).  I do have lots of electrical wiring "stuff" too (switches, breakers, sockets, boxes, conduit, fittings, wire, etc) and have some old plumbing fixtures (toilets, urinals and sinks) and some diesel engines, both air cooled and liquid cooled and a nice collection of Yamaha G1 golf carts (three two stroke gas and 1 electric) plus one Yamaha G3 two stroke gas, all from the early to mid 1980s.  I have a pretty good music collection, including lots of vinyl, cassettes and CDs. My barn also has lots of lumber stored away for future projects and many pallets of firewood.

@Dieselnut, you mentioned cassettes and it reminded me... I have a small collection of cassettes as well, although it
wasn't really my intention. They just stuck with me during each move. They're gonna stay with me forever though, because
I've got a lot of recordings in each cassette tape from when I was a kid. A lot of audio experimenting, from a kid's perspective.
I've also got a small collection of books I've created as a kid, and books I've read as a kid as well.

I used to collect old-school audio electronics.

Recently I sold most all of it on eBay when I realized my family would just recycle it if I die. Didn't get as much money as I would have thought!

I still have 2 very old-school, high-end Pioneer audio receivers (SX-1050 and SX-636) old JVC high end cassette deck, Technics turntable, Bose speakers, Pioneer HPM-100's. I have also restored all of them except for the speakers.

I guess, I also "collect" vinyl records and cassettes, but not seriously. I just buy whatever I like and play it on my old equipment. Oddly, they still press new albums for this stuff, and even more oddly you can still get new releases on cassette. I recently bought a cassette, Guardians of the Galaxy, and strangely enough, it sounds quite good on my old JVC deck! Oh, and my Mom gave me all of her old albums recently, Tina Turner, Prince, Police, Fleetwood Mac, etc, about 40 albums.

I found that maintaining my current collection of gear aforementioned is more than enough work, and instead of hoarding everything else, I put the other stuff up to auction to let others enjoy it. I don't collect any more since then.

Oh, and I do collect traffic signals (2 is all I have these days) but they are kind of "lighting"

Fleetwood Mac is awesome.

Lots and lots of gear, flags, and souvenirs from Iceland and Colorado

along with lighting (mostly mv) I have a few old jukeboxes (only 1 currently works), lots of old radios (vacuum tube style only), old cars, maybe someday I'll be able to afford to restore  all of this, (I doubt it) but hey, at least I have it!

Also collect wiring devices, and have a few old computers as well.

Computers, bikes and electrical bits.

Fleetwood Mac is awesome.

I have met Stevie Nicks several times.When I was very young, my uncle was a service manager at Tony M. Coury Buick in Mesa, AZ. I first met her then because she drove Buicks at that time. My music teacher had her poster in our classroom, so that was interesting to me.

When I grew older, I worked at Kachina Cadillac in Scottsdale, AZ. Stevie had a Cadillac that she would have serviced there, and twice I got to drive her home as a courtesy, and once I got to deliver a car to her.

To me, that seems like FOREVER ago (1/4 century!) but Stevie is still out there, looking good and making music. I feel like I aged more dramatically than she has!

Yes! I collect some cables, and I use it 

I collect locks, miscellaneous small vintage electronics, tiny road parts (reflectors, etc.), wire nuts, and service equipment.

I don't actively collect on these, but I do it when I have a chance!

Cool ! I collect locks as well. What is your favourite brand ?

Cool ! I collect locks as well. What is your favourite brand ?

I like Abus the most, but I can't find their locks anywhere (besides online) here. I have only one and it's a combination lock. The only place that I know uses them is my local utility company (SCE-Southen California Edison). Master is a good brand too and I have quite a few but wished they make their cores more secure (most of them, even the $40 dollar ones) have only standard pins.

I have met Stevie Nicks several times.When I was very young, my uncle was a service manager at Tony M. Coury Buick in Mesa, AZ. I first met her then because she drove Buicks at that time. My music teacher had her poster in our classroom, so that was interesting to me.

When I grew older, I worked at Kachina Cadillac in Scottsdale, AZ. Stevie had a Cadillac that she would have serviced there, and twice I got to drive her home as a courtesy, and once I got to deliver a car to her.

To me, that seems like FOREVER ago (1/4 century!) but Stevie is still out there, looking good and making music. I feel like I aged more dramatically than she has!

WOW.. Thats pretty awesome!

I collect locks, miscellaneous small vintage electronics, tiny road parts (reflectors, etc.), wire nuts, and service equipment.

I don't actively collect on these, but I do it when I have a chance!

I have a few road things too like signs and reflectors. I started collecting reflectors before I started with lighting, so I have hundreds of them. I still pick some up every now and then. The best time to get road signs is after tropical storms and hurricanes when they’re all blown away!