Sega Mark III, which itself was the third iteration of Sega's real first foray into hardware design, the SG-1000.
The SG-1000 (an acronym of "Sega Game" 1000) was released in Japan on July 15, 1983 for ¥15,000, which at the time amounted to $62.48 USD, assuming an average exchange rate of ¥240.06 to the dollar. (Coincidentally, this was the also the day that Nintendo launched the Famicom.) Armed with a blistering 3.5 MHz CPU and two whole entire kilobytes of RAM, the SG-1000 was only mildly successful in Japan, Australia and New Zealand, but curiously saw much greater success in the piracy-infected Taiwanese market.
North America, however, never saw an official SG-1000 release, although the Telegames Personal Arcade was released stateside and was capable of playing SG-1000 carts, had they somehow managed to make the trip across the Pacific. The SG-1000 Mark II was released a year later in 1984, sporting a redesigned case and identical components (sound familiar?). Nowadays, Mark I versions of the SG-1000 can go on eBay for as much as $1,500 – a good bit more than the 63 bucks it would have run you back in 1983.