http://www.dvc.org.uk/~johnny/jeff/jeff4_15.html
In a recent adventure appearing in one of the science fiction magazines, the author postulates time travel and suggests that his protagonist, when wafted back into the late Stone Age, was able to bring along his own personal fancied-up Colt Commander in 45, and that his subsequent adventures gave rise to the legend of Mjðlnir, the Hammer of Thor. That's an entertaining thought, as it re-states the question that many of us have considered in our reading of time travel fantasy in general.
Knowing what you do about smallarms, what piece that you now own would you choose to accompany you back into days gone by? This may be worth a small bull session.