It might have only been a pilot or a made for TV movie, but I remember a male time traveller who was for some reason in 90s US from a semi-distant future. He had in his possession a super-computer disguised as a regular credit card, which could hack things and I think spoke to him in a female voice.
Note: Not Quantum Leap - the time traveller and "credit card computer" might be keywords that people would hit upon, but 'Ziggy' the computer in QL was non-speaking, operated by a hologram and did not resemble a credit card - this one had its own voice and was disguised as a CC.