Bicycles are ubiquitous on most city streets, but that doesn't mean they have to be boring. Over the years we've seen some absolutely bizarre bike designs.

The Dinocycle

It’s a tricycle, but also a dinosaur. What’s more fun than that? Norwegian artist Markus Moestue invented this unusual vehicle using parts from several individual bicycles. The result is a trike with the neck and head of a dinosaur that lived around 200 million years ago during the latter part of the Triassic period. Moestue took six months to build his dinocycle for a trek across Norway, but he reportedly put it up for sale before the trip could happen

The Russian chainsaw bike

Little is known about this danger-mobile, since photos of it originally surfaced on the web several years back. Apparently built in Russia, the bike has a working chainsaw fixed to the front wheel, with all the sharp bits pointing forward. From the photo, the "attack bike" evidently uses the chain drive to power the front tire. There are apparently lots of other ways to fuse a chainsaw with a bicycle: A quick web search will reveal far more results than you might predict.

The Fliz Bike has no pedals

Most bikes are pedal-powered. What happens when they aren’t? The Fliz Bike trades a seat for a bizarre torso harness and, instead of pedals and gears, there's... nothing. Riders of the Fliz Bike keep their feet on the ground, for the most part, in what we can only describe as the bicycle equivalent of a Flintstones car.

The Twicycle is a whole body workout

The Twicycle is a bizarre bike design that guarantees a killer workout. Instead of being propelled entirely by leg action, this bike can be driven by your arms too. In that setting, the rider leans forward, bracing the torso on a comfortable chest pad that's designed to keep core muscles tight and distribute the workout to the shoulders, biceps, lats, back and abs. Crowdfunding efforts are underway to launch the adjustable, unisex bike, which offers a balanced outdoor workout for anyone who wants it.

The world's first flying bike

A pair of British inventors created what is easily the world’s first flying bicycle, the Paravelo. Alone, it’s more or less just a bike, but it can also be attached to the optional trailer which carries a giant fan and huge parasail. With the trailer mounted, the designers say it can fly up to 4,000 feet above the ground, which is tough to believe if you haven’t seen it. Video of its 2013 maiden flight is all the evidence needed to prove how amazing this bike is.

The Rungu Juggernaut is a fatbike on steroids

What do you call a bike with three wheels that isn’t a tricycle? A Juggernaut, for sure. Like a mountain bike on steroids, the Rungu Juggernaut bike has two knobby tires in front, positioned right next to one another. The soft wide tires carry the bike easily over the most difficult of terrain -- even sand and snow. That makes it possible to trek where even the most robust fatbike can’t go. The $2,500 bike might bust your budget, but imagine the priceless adventures it could bring.