The Sparrows UNCUFF LINK cufflinks look like normal accessories when they're in your sleeves, but pop them out and you can use them to unlock and open any pair of standard handcuffs, thanks to the key engineered into the body. We're not going to ask how you got into those cuffs in the first place, but no good superspy would be caught unable to get out of them.
The Uncuff Links are available for $US59 as pre-orders and $US69 when they start shipping on the first week of December (sans shipping.) Sparrow notes that they work on standard cuffs only, and just in case you needed us (or them) to tell you, don't break the law or use these to try and escape the police, okay? This is the kind of accessory you carry because you want to feel like a spy, not act like one.
Even when they're not helping you perform escape acts or get revenge on the room mate who cuffed you to the bed, they look pretty good keeping your French cuffs closed.
Update: There's now an Australian source as well.