I used to have my passenger hold onto my belt, when i wore jeans and a short jacket. More recently I wear riding pants and a longer jacket that doesn't expose a belt. Just saw this product on our local Sunday night motorcycle show.
http://grip-n-ride.com/You can wear the belt with the grips in front or back. It doubles as a kidney belt, which I often wear anyway, though not often on the outside of my jacket.
No pricing, I can't get the rest of the site to work.