IBM mainframes. Smurfs, Ewoks, and other forms of offensive cuteness. Bureaucracies. Stupid people. Easy listening music. Television (except for cartoons, movies, and "Star Trek" classic). Business suits. Dishonesty. Incompetence. Boredom. COBOL. BASIC. Character-based menu interfaces.
:Food: ======
Ethnic. Spicy. Oriental, esp. Chinese and most esp. Szechuan, Hunan, and Mandarin (hackers consider Cantonese vaguely d'eclass'e). Hackers prefer the exotic; for example, the Japanese-food fans among them will eat with gusto such delicacies as fugu (poisonous pufferfish) and whale. Thai food has experienced flurries of popularity. Where available, high-quality Jewish delicatessen food is much esteemed. A visible minority of Southwestern and Pacific Coast hackers prefers Mexican.
For those all-night hacks, pizza and microwaved burritos are big. Interestingly, though the mainstream culture has tended to think of hackers as incorrigible junk-food junkies, many have at least mildly health-foodist attitudes and are fairly discriminating about what they eat. This may be generational; anecdotal evidence suggests that the stereotype was more on the mark before the early 1980s.
:Politics: ==========
Vaguely liberal-moderate, except for the strong libertarian contingent which rejects conventional left-right politics entirely. The only safe generalization is that hackers tend to be rather anti-authoritarian; thus, both conventional conservatism and `hard' leftism are rare. Hackers are far more likely than most non-hackers to either (a) be aggressively apolitical or (b) entertain peculiar or idiosyncratic political ideas and actually try to live by them day-to-day.
:Gender and Ethnicity: ======================
Hackerdom is still predominantly male. However, the percentage of women is clearly higher than the low-single-digit range typical for technical professions, and female hackers are generally respected and dealt with as equals.
In the U.S., hackerdom is predominantly Caucasian with strong minorities of Jews (East Coast) and Orientals (West Coast). The Jewish contingent has exerted a particularly pervasive cultural influence (see {Food}, above, and note that several common jargon terms are obviously mutated Yiddish).
The ethnic distribution of hackers is understood by them to be a function of which ethnic groups tend to seek and value education. Racial and ethnic prejudice is notably uncommon and tends to be met with freezing contempt.