If it's a small amount (IE Less than $100 AUD if converted) I have a large old balance scale in my family room that I put it in (on?). It's probably about time I had a look at it because it would be a burglar's dream. There's probably a few thousand dollars in it now.

For larger amounts, I have a several envelopes in my home safe with various countries names on them and I keep travel items for that location, including spare currency, power adaptors, maybe maps, etc in them. When I'm going to a specific location, I'll grab the envelope for that area and pretty much be ready to roll once I get off the jet.