1. An integer number representing the number of items hanging from a batbelt. In most settings, a Batman factor of more than 3 is not acceptable without odd stares and whispering. This encourages the hacker in question to choose items for the batbelt carefully to avoid awkward social situations, usually amongst non-hackers.
2. A somewhat more vaguely defined index of contribution to sense 1. Devices that are especially obtrusive, such as large, older model cell phones, “Pocket” PC devices and walkie talkies are said to have a high batman factor. Sleeker devices such as a later-model Palm or StarTac phone are prized for their low batman factor and lessened obtrusiveness and weight.