https://countycomm.com/products/cage...cket-led-light
I gave these pocket lights out as stocking stuffers last year and everyone liked them. A 10 pack is $16 which would give one person enough to put in every coat pocket (or attach to zippers), on every key chain, and in every vehicle. If not for the BIL, perhaps for others.
They come with batteries in them and a split ring attached. The batteries can be replaced (1x CR2032; or, 2x CR2016) by removing 4 screws with a jeweler's (eyeglasses) screwdriver. It's sturdy (industrial contract overrun) and designed without any sharp edges to snag on clothing. This website has other interesting stuff if you go through the menu.
If you want to spend big bucks to wish him good luck with Brexit, go with this:
http://www.royalmint.com/shop/The_Silver_Sixpence_2016