Wow. Is there enough bandwidth? I have been accused of having motorcycle/car ADD. Oh look, a puppy...
In sorta chronological order, starting at age 5:
No name minibike, blue with red lawnmower engine
Rupp minibike
Honda Mini Trail
Honda SL70
Honda SL100
Honda SL175
Honda SL125 (3 of those)
Honda XL175
Honda Elsinore 125
Harley 900 Sportster (a real piece of shit, that one)
Honda XL350
Yamaha TT250G
Yamaha Seca 750
Honda CL360
Yamaha TT600
Honda XR250 (2 of those)
Honda XR600 (heavy as hell but fun)
Honda XR400R (underpowered but a great bike)
Hodaka 100B
Hodaka Super Rat
Yamaha WR400F (LOVED this bike!)
1980 XS650 (current ride).
Had a bunch of various parts bikes, probably 20-30 of those. And I am sure I have left a few out, too.
Cars?
1965 Falcon, first car.
1971 Dodge Charger (an absolute gas hog.)
1971 Pinto
1972 Pinto (3 of those)
1974 Pinto
(For a while I bought Pintos cheap, drove them and resold them for a profit.)
1978 Plymouth Arrow
1974 Mustang II (a complete turd)
1968 Triumph Spitfire (swapped a 2.0 German Ford engine into it, REAL quick car)
Various Spitfire parts cars, 8-10 total. Most I fixed and sold for a profit.
1957? Triumph Herald convertible (ugliest car I ever owned)
1970 Triumph GT6+ (scary evil handling thing but man would it go)
1972 Triumph TR6
1971 MGB
1972 MGB (3 of those)
1973 Ford Courier pickup
1978 Ford Fiesta (great car, too bad it got totaled by a Buick)
1983 VW Rabbit GTi (the worst POS I ever owned. That car actively tried to kill me.)
1978 Datsun 280Z
1979 and 1981 Fiat X 1/9's (fragile but FUN!)
1979 and 1982 Mazda RX7's
1993 RX7 (totaled, bought it to part out.)
1986 1/2 Nissan SE V6 4x4 (my favorite truck)
1991 Isuzu Amigo XS (cool looking, fun but way underpowered)
1992 Jeep Cherokee Sport (a REAL pile of shit, was I ever glad to see it go)
1994 Isuzu Rodeo 2wd (great vehicle)
1974 Jensen Healey restored (still have)
1980 Triumph Spitfire with Mazda 12A rotary
1974 Jensen Healey with Mazda 13B rotary (still have, sold the rotary Spitfire to bankroll this one)
1997 Isuzu Trooper (still have, most reliable thing I've ever owned)
I'm sure I have left off a few various vehicles, like the Honda Odyssey (not the minivan!) I co owned with my brother, various go carts, crap like that.
EDIT: Yup, forgot to mention my 1971 Porsche 914. Had to be the slowest 'sports' car I ever owned. I could outrun it on foot.
ANOTHER EDIT: Forgot my Datsun powered 1970 Spitfire. Fun, handled great and best of all RELIABLE!