Try using the double layer of fabric at the top of your pants. I made a slit - essentially a large button hole - inside the waist band of several pairs of jeans and a pair of slacks when we took our honeymoon. I used the gap between the layers of fabric to hide our reserve of folded paper money, sliding the bills in kind of like the drawstring in a pair of sweat pants. I figured bad guys knew about neck/waist pouches, zippered belts, room safes, etc...

When you wear a belt or un-tucked shirt, no one can see any sort of lump or bulge in your pants, and I never felt a thing. Unless subjected to a strip search and close examination of your clothes, no one will ever know you've got a hiding place. I personally wouldn't keep a blade there, but there's as much or more room there than in one of those 'survival belts' that used to be on the market (I forget the source). The only drawback I found was it isn't rapid/easy access. You need some privacy and a few minutes to access your cash/stash. Oh yeah, and try not to lose your pants...