Thanks bobreedo. I believe the U.S., when a person is disposing of their non-primary currency, they are deemed exchanging property (the non-primary currency) and may have a gain (potentially, even it was for personal use and over $200). Further, these related gains may default to ordinary tax rates instead of capital. So currency could be a worse answer depending on the facts/circumstances, I do plan to have a "what if it was currency" and "what if it was a security" subsection to keep score better in case the government changes positions.

Edit Disclaimer - this is not tax advice and can't be used to avoid taxes/penalties (I keep forgetting to add this!)