My brothers were doing a Google search of their Casio watches, and to his surprise Aonghas found out that he's wearing the 'watch of terrorists', the Casio F91W!
According to Wikipedia:
"This model of watch is notable because United States intelligence officials have identified it as the watch that terrorists use when constructing time bombs. Ahmed Ressam, the millennial bomber, bought two Casio F91W"
"...it became known that the allegations against approximately one dozen of the Guantanamo detainees justified their continued detention because they had been wearing this model of watch, when captured"
However, Casio issued a statement saying that this particular watch has "no exclusive technology" and that "Casio continues to work closely with all government agencies, including the Department of Homeland Security to help limit any potential threats and deal with security concerns."
A list is then provided of a few detainees who were held for wearing this particular type of Casio watch, with some of the reasonings being:
"The detainee was captured while in possession of a Casio watch model that has been used in bombings linked to al Qaida and radical Islamic terrorist groups with improvised explosive devices."