Kaiji - Ultimate Survivor

Itou Kaiji is a bum who steals car emblems and slashes tires on what seems to be a regular basis. This routine changes one day when he is paid a visit by a man in a trench-coat. Once the two get talking, it seems that the visitor (Calling himself Endou) is a debt collector. The reason for his visit is an unpaid loan which Kaiji had previously co-signed for a work-mate (Furuhata Takeshi). The original loan was 300,000 yen and once Takeshi had disappeared, the loan then fell on Kaiji. Kaiji is then told of a way to clear the interest compounded debt (which stood at 3,850,000 yen), which involved getting on a boat with others in his position. Once on the boat the debtors would then have to gamble with loaned money, which would end with a few winning, and others getting into deeper debt and having to work to pay off their debts. After some coercion Kaiji accepts a position on the boat, in order to clear his debt and make a bit of money as well...

Touhai: Ura Rate Mahjong Touhai Roku

Money, women, organs. Kei, a high school boy, frequents the underground mahjong parlor teeming with desires, earning him the moniker 'K of Ice' in the underworld due to his cold-hearted strategy and stylish gameplay. Rumors also circulate that he keeps a girl at his home. (Source: Pony Canyon)

One Outs

The story begins when Hiromichi Kojima, the star batter of the fictional Lycaons in Japan's Pacific League, heads to the southern Japanese island of Okinawa to train and bring himself out of a slump. There, he meets Toua Tokuchi, a 134-kmph (83 miles per hour) pitcher and the undisputed king of a gambling form of baseball called "One Out." At Kojima's urging, Tokuchi signs up with the Lycaons under an unusual contract: he gets 5,000,000 yen (about US$46,000) for every out he pitches, but loses 50,000,000 yen (US$460,000) for every point he gives up. (Source: Anime News Network)

Saki

Miyanaga Saki is a first year high school girl whose family would get angry if she won the family mahjong games. But losing would also have its consequences. Because of this she develops a new way of playing that allows her to stay on the thin line between winning and losing, the plus/minus zero score, an almost impossible score. In a game that relies mainly on luck, the plus/minus zero score is harder than winning, but Saki can achieve this every time.Having always hated the game, her friend from middle school, Suga Kyotoro, forces her to play in the schools mahjong club. Her developed skill and superhuman luck has made her a worthy mahjong opponent, even to the middle school's national mahjong champion.(Source: Anime News Network, edited)