Japan uses vending machines for everything from train tickets (they accept ¥10,000 notes, hard to imagine paying for a NYC subway token with $100), beer, pre-cooked spaghetti, and manga to a high school girl's old underwear [ The Daily Yomiuri. "Dealers of Used Female Underwear Charged." 21 September 1993 (p. 2); Mainichi Daily News. "'Bura-Sera' Vending Machines Stir Local Concern." - Buru (blue) Sera (sailor - refering to the style of the high-school uniform) 12 September 1993. ] (this is rare). The degree to which vending machines replace human interaction (underwear aside) is evident in the substantial percentage of foreign expats who, despite years of living in Japan, do not want or need to speak the local language. For the casual visitor with no specific agenda, the drink machines prove the most useful.
Always note the beer and sake machines in the vicinity of your hotel, as they can come in handy after dinner if you feel like relaxing in your room in front of some first-rate Osaka TV, always a good way to get a bit of insight into a culture. Contrary to North American Suburbia, where youths spend hours waiting around the side of a 7-11 for someone kind enough to buy them beer, and stories of alcohol vending machines in the Far East were laughed off as a near-physical impossibility, the alcohol vending machines are not used/abused by thirsty youth, who associate alcohol with the stumbling, uncool, drunken 'salarymen' (their fathers). The prices of beer and tobacco in Japan are the same in all stores and vending machines nationwide, though alcohol vending machines stop vending at 11pm.
Eight hours later you may be thinking more about the canned coffee, which comes in all combinations, and in winter either hot or cold (the hot cans make good hand-warmers too, and make you wonder why we can't do this back home). Canned creamed corn soup is probably the overall favorite vending machine food, though spaghetti is not uncommon (not sure how this is dispensed).