Well of course these links do that job too. They're from Bouf (the link is to the whole range of cufflinks, they have some seriously unusual stuff) and - wait for it - the balls are actual pistol shot from - it says here - the English Civil War. We are not talking reproduction or facsimile, a Roundhead shot this at a Loyalist or the other way around. Each set comes with a written account of where they were found - but yes, your cufflinks could have been used as a deadly weapon sometime in the last half-millennium if you're wearing these.
Good grief I want a pair of these. Just remind your partners we're all big kids at heart and these are genuine antiques and actual bullets!
My competition to nominate the worst ever Christmas song ends on Friday. Entry is free and here are the details - someone has to win all these prizes!