PixlBit

The Atari 2600 was the first successful mass-market console to feature a library of interchangeable games, and the first successful home console to offer an experience beyond Pong. But Atari was not alone. The Fairchild Channel F beat the 2600 to market by a year but crashed and burned. If any of Atari's early competitors is remembered, it will most likely be the Mattel Intellivision, a brand which famed game producer Tommy Tallarico is trying to resurrect. In third place was Magnavox's Odyssey2, whose best-selling title, K.C. Munchkin!, was the object of a lawsuit by Atari over its similarity to Pac-Man, which Atari had gone to a lot of trouble to license from Namco. 

There was a fourth competitor, which was a system that in many ways is worthy of the cliche, "ahead of its time." This was the Bally Professional Arcade. Manufactured by Bally, a Chicago-area firm that had a wide variety of disparate business lines similar to Konami in Japan, the Professional Arcade was only sold by Bally for a short time, then sold off to another company which marketed it as the Astrocade until shortly after the 1983 video game crash. 

Bally ultimately hoped to market the Professional Arcade as a starter home computer. It was meant to look like an AV component. It came with a free BASIC cartridge and sported a calculator-style keyboard on the console which could either be used with BASIC or with the game library. There was a full keyboard add-on available at some point. The game cartridges were deliberately sized and shaped like audio cassettes and slipped into the cartridge slot like cassettes.  The Professional Arcade featured storage space on the console itself for video game cartridges.

The Professional Arcade was considerably more powerful than most other game hardware at the time. One of Bally's business lines was Bally/Midway, the arcade manufacturer which would be later known for Mortal Kombat. Therefore, the Professional Arcade attempted to live up to its name by having powerful enough hardware to provide experiences close to coin-operated arcade machines, and drew upon the extensive library of Bally/Midway games and licenses, which included at the time Space Invaders, Galaxian, and Gun Fight. Space Fortress was a home port of Bally's Space Zap, which was an inverted version of Star Castle. The crown jewel of the Professional Arcade is generally considered to be The Incredible Wizard, a home version of Bally's arcade game, Wizard of Wor, that is very close to the arcade original in terms graphics and sound.  

Controllers hadn't really been codified by that point, so early consoles sported some unusual designs. The Atari 2600 and Odyssey2 both featured the familiar joystick-fire button controllers based on the arcades, while Intellivision, the 5200, and Colecovision featured complex controllers with telephone-styled keypads and unusual controllers. The Intellivision and Colecovision's controllers combined joystick functions (two-axis controls) with disc functions (movement along a single axis in Pong-style games), while Atari marketed a separate set of "paddle" controllers for the 2600.

Even by these standards, the Bally controller was an odd beast. Guns and shooting games were very popular on early consoles - the original Odyssey had a light gun shaped like a somewhat realistic pump-action shotgun that video game manufacturers woul never be allowed to get away with today. The Bally controller definitely reflected that mindset. It was shaped like a pistol grip, with the fire button being the trigger. At the top of the pistol-grip was a knob which both moved along X-Y axes and twisted like a paddle controller. Even the weirdest modern controllers couldn't hold a candle to this bizarre contraption. These days, though, the rear shoulder buttons on modern controllers are trigger-shaped, a convention that arguably began with the Z button on the N64 controller, so Bally was definitely onto something.

On its release in 1977, the Professional Arcade was initially sold by mail-order only before it was released to retail some time later. It never sold in huge numbers and Bally soon sold the rights to the console to another company, which rebranded it as the Astrocade. Here's a confession: I had the opportunity to buy a Professional Arcade at a store in north Phoenix called Fallout games. It was only $150. I failed to take the opportunity to buy it, and it eventually got sold to someone else. So I will likely never see one of those again unless I'm willing to pay $200-400 bucks on eBay. But it's really too bad this never caught on, because in terms of power, it was largely unmatched until the NES and Master System entered the market. Price and limited marketing/availability doomed it to fourth place behind the 2600, Intellivision, and Odyssey2.